The Traditional Way Of Learning In the olden days, you had to go to school or college to educate yourself. In the classroom, listen to the lectures, make notes and enjoy some discussions with the lecturer and classmates. At home, you would refer to textbooks and complete the work suggested in the curriculum. Other than college, you had and have the option of private tuition. There are many brick and mortar training academies that supplement the colleges and universities.

Data Structures And Algorithms Data Structures: A data structure is a technique of storing data in a computer so that it can be accessed and modified efficiently. Algorithms: An algorithm is a step-by-step instruction to perform a task. Why Should I Learn Data Structures And Algorithms? Enhance your problem solving skills. Write efficient code that is performant and scalable. Specialized fields: machine learning, data science, artificial intelligence and other engineering fields deal with complex data and require efficient processing.

A reference application is a sample application that is used as a guide for developers to learn and implement best practices for software development, testing, deployment, and operations within a specific technology stack or framework. It can serve as a blueprint for building and maintaining similar applications and can be used to demonstrate the use of tools, processes, and techniques for achieving high levels of automation, scalability, and reliability. If you are learning how to deploy applications to Kubernetes of Virtual Machines in cloud, create your own tiny application.

I see a lot of people are trying to break into software engineering and DevOps. There are many inspiring stories out there. People from other industries and verticals have switched to IT and are having a successful career. You can do it too. Let us look at the resources available to you. Online Vs. Offline Training And Learning Resources Online All you need to break into DevOps is: A laptop or a desktop computer Internet connectivity A quiet place Time Motivation that’s all.

Introduction If you have chosen the DevOps engineering path for your career, Linux system administration skills are a must. Companies run their workloads on Linux on-premise as well as in the cloud. Many developers write software on their Linux laptops and workstations. In this post, I will lay out a plan to master Linux system administration skills. The journey begins with you becoming a Linux desktop user. Gradually, you start using your laptop as a Linux server.

Learn Linux. Install Linux on your laptop. Get familiar with Linux commands. Learn virtualization. Unlock the path to learn more Linux. Programming. Acquiring some programming skills using a general purpose programming language like Python goes a long way. Learning some web development is required in most DevOps engineering contexts. Although you don’t have to be an expert in web development, you should have a clear understanding of workloads consisting of web applications and microservices.

The List Of Web Application Ideas An e-commerce platform where people can buy and sell products online. A platform for booking and managing doctor’s appointments. A social networking site for connecting with friends and family. A task and project management tool for teams and organizations. A recipe and meal planning app for people who want to eat healthy. A travel planning and booking app that helps people plan their trips and find the best deals on flights and accommodations.

The blog post attempts to answer some questions like: How to become a DevOps engineer? How to prepare for a DevOps engineer interview? How to get a DevOps engineer job? In a previous blog post, I wrote about the path an aspiring DevOps engineer could follow. In this blog post, I will lay out a concrete plan using which you can prepare yourself for a DevOps engineer job. If you follow the steps carefully, you will be armed with practical DevOps knowledge, and you will be able to apply for DevOps engineer jobs confidently.

The build and deploy engineer is a role in IT/infrastructure/devops teams of organizations that is responsible for deploying a set of applications using CI/CD pipelines. Usually, they use the pipelines, tools and processes created by DevOps engineers, consultants or practitioners. They tweak things with tools like Ansible, Jenkins, Git, Maven, etc. here and there a bit. Are you one such build and deploy engineer looking to transition your career into DevOps engineering?

AWS Certified Solutions Architect - Associate is one of the most sought-after certifications in the IT industry. Here’s a few tips for those seeking this certification. Background Knowledge And Experience AWS recommends “at least one year of hands-on experience designing available, cost-efficient, fault-tolerant, and scalable and distributed systems on AWS.” In other words, if you recently started your career in IT, there are a few things you have to do before you start preparing for this certification.

The Traditional Way Of Learning In the olden days, you had to go to school or college to educate yourself. In the classroom, listen to the lectures, make notes and enjoy some discussions with the lecturer and classmates. At home, you would refer to textbooks and complete the work suggested in the curriculum. Other than college, you had and have the option of private tuition. There are many brick and mortar training academies that supplement the colleges and universities.

The Traditional Way Of Learning In the olden days, you had to go to school or college to educate yourself. In the classroom, listen to the lectures, make notes and enjoy some discussions with the lecturer and classmates. At home, you would refer to textbooks and complete the work suggested in the curriculum. Other than college, you had and have the option of private tuition. There are many brick and mortar training academies that supplement the colleges and universities.

When you begin your career in IT, you will be required to learn Git sooner or later. Git is a key technology used in everyday software engineering and DevOps. It has become persuasive and quintessential. There is no need to hard sell Git to anyone at this point. There is a lot to learn about Git. The good news is that you can start with a subset of Git. There is a no need to become a Git master on your day one of software engineering or DevOps engineering.

I see a lot of people are trying to break into software engineering and DevOps. There are many inspiring stories out there. People from other industries and verticals have switched to IT and are having a successful career. You can do it too. Let us look at the resources available to you. Online Vs. Offline Training And Learning Resources Online All you need to break into DevOps is: A laptop or a desktop computer Internet connectivity A quiet place Time Motivation that’s all.

Data Structures And Algorithms Data Structures: A data structure is a technique of storing data in a computer so that it can be accessed and modified efficiently. Algorithms: An algorithm is a step-by-step instruction to perform a task. Why Should I Learn Data Structures And Algorithms? Enhance your problem solving skills. Write efficient code that is performant and scalable. Specialized fields: machine learning, data science, artificial intelligence and other engineering fields deal with complex data and require efficient processing.

Data Structures And Algorithms Data Structures: A data structure is a technique of storing data in a computer so that it can be accessed and modified efficiently. Algorithms: An algorithm is a step-by-step instruction to perform a task. Why Should I Learn Data Structures And Algorithms? Enhance your problem solving skills. Write efficient code that is performant and scalable. Specialized fields: machine learning, data science, artificial intelligence and other engineering fields deal with complex data and require efficient processing.

Data Structures And Algorithms Data Structures: A data structure is a technique of storing data in a computer so that it can be accessed and modified efficiently. Algorithms: An algorithm is a step-by-step instruction to perform a task. Why Should I Learn Data Structures And Algorithms? Enhance your problem solving skills. Write efficient code that is performant and scalable. Specialized fields: machine learning, data science, artificial intelligence and other engineering fields deal with complex data and require efficient processing.

Purpose Of Having Naming Conventions For An Ansible Project Consistency: Adopting a naming convention standardizes naming across the project and organization. This makes it easier for developers to switch between projects. Typically, an organization with an infrastructure team will have several Ansible projects and source code repositories. A developer working on one such Ansible project can seamlessly switch to another given a standard naming convention. Error Reduction: With improper naming there can be pitfalls.

A reference application is a sample application that is used as a guide for developers to learn and implement best practices for software development, testing, deployment, and operations within a specific technology stack or framework. It can serve as a blueprint for building and maintaining similar applications and can be used to demonstrate the use of tools, processes, and techniques for achieving high levels of automation, scalability, and reliability. If you are learning how to deploy applications to Kubernetes of Virtual Machines in cloud, create your own tiny application.

In the Kubernetes Objects Required For A Typical Web Application post we talked about few Kubernetes objects that a web application developer should get accustomed to. In this post, we will extend the series and talk about more objects that can help web developers scale their applications. As we delve deeper into Kubernetes topics, the demarcation of roles and skill sets start to reveal. In larger organizations, a dedicated team of infrastructure engineers design and make choices of network topology, IAC tooling and orchestration of the Kubernetes clusters and CI/CD pipelines.

In a previous post, we discussed using age to manage secrets in Git repositories. In this post, let’s improve our secrets management workflow in Git repositories using SOPS. sops is an editor of encrypted files that supports popular configuration formats such as YAML and various encryption techniques such as age. Read the blog post about age to install the package and creating the key file. This time, we will use sops to perform encryption and decryption operations instead of the age command.

Are you storing secrets such as database credentials, API keys, etc. unencrypted in Git repositories? Stop. To protect your secrets, do not store them anywhere unencrypted. Especially in Git repositories. Ideally, your organization must have some vault solution where secrets can be stored and securely shared with people on a need-to-know basis. In many small organizations, having such a central secrets management solution is still a luxury. The need to store such secret information in Git repositories is obvious.

From an application developer and Kubernetes user’s point of view, you have to have a working knowledge of Kubernetes. The post outlines the most important Kubernetes objects required to deploy a typical web application. Let us assume that the web application uses the two-tier architecture. We also assume that the cluster is created and administered by an infrastructure or DevOps engineer and the necessary access is provided to the developer to deploy their web application onto the Kubernetes cluster.

The List Of Web Application Ideas An e-commerce platform where people can buy and sell products online. A platform for booking and managing doctor’s appointments. A social networking site for connecting with friends and family. A task and project management tool for teams and organizations. A recipe and meal planning app for people who want to eat healthy. A travel planning and booking app that helps people plan their trips and find the best deals on flights and accommodations.

In this blog post, I will explain how I implemented a graph algorithm to solve the database migration problem in an application pluggable module system. Prerequisites: Working knowledge of Python Working knowledge of Graph Theory. Familiar with the terms: Edge, vertex, path, sink, source, digraph, path graph, etc. Gavika Web Framework has a pluggable module system. The modules can be developed independently. They can be installed, upgraded and removed from the main application.

You access Python dictionary keys using the syntax: my_dicy[my_key] For example: >>> my_dict = {'food': 'idly'} >>> my_dict['food'] 'idly' Sometimes, you might want to access the dictionary keys using: my_dict.my_key syntax. If you do this is what happens: >>> my_dict.food Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'dict' object has no attribute 'food' How can you solve this? Easy. pip install attrdict How do you use the newly installed package?

Introduction This is an anchor post about machine learning and artificial intelligence. Observations On AI Revolution in Text Generation: Generative AI is making significant strides in text production, promising a surge in the quality and quantity of text-based content. This encompasses everything from blog posts and articles to comprehensive reference books, transforming how information is created and disseminated. Advancements In AI-Generated Imagery: The evolving capabilities of AI in image generation are noteworthy.

Introduction This is an anchor post about machine learning and artificial intelligence. Observations On AI Revolution in Text Generation: Generative AI is making significant strides in text production, promising a surge in the quality and quantity of text-based content. This encompasses everything from blog posts and articles to comprehensive reference books, transforming how information is created and disseminated. Advancements In AI-Generated Imagery: The evolving capabilities of AI in image generation are noteworthy.

In a previous series of blog posts, we discussed the Kubernetes objects typically used to run a web application. We covered, Namespace, Pod, ConfigMap, Secret, Service, Deployment, ServiceAccount, Ingress, PDB, HPA, PV, PVC, Job and CronJob. In this post, we will discuss some fundamental building blocks for the Kubernetes cluster administration: RBAC objects. In most situations, Kubernetes API server is started with the flag --authorization-mode=RBAC which enables RBAC in the cluster.

Introduction We have the host machine with the OS Ubuntu 22.04. On this PC or server, we will create two virtual machine guests: myubuntu2204test01 having static IP of 192.168.122.146 myubuntu2204test02 having static IP of 192.168.122.147 The guest VMs will use the default network created by libvirt. The gateway IP for the default network is 192.168.122.1. We will achieve automation using libvirt, qemu and cloud-init. To go through the article and exercise, you should have a rudimentary understanding of Linux system administration and networking.

Using Linux KVM, Expose Virtual Guests On The LAN Audience: The blog post is for beginner to intermediary Linux system administrators. You should have a thorough understanding of the shell commands and be comfortable on the command line be able to install and configure packages, etc. be able to start and stop services using systemd be familiar with Linux configuration files be able to set Linux kernel parameters using sysctl be able to enable and disable Kernel modules be comfortable installing and using guest VMs using libvirt You should have a rudimentary understanding of networking concepts and tooling such as

Purpose Of Having Naming Conventions For An Ansible Project Consistency: Adopting a naming convention standardizes naming across the project and organization. This makes it easier for developers to switch between projects. Typically, an organization with an infrastructure team will have several Ansible projects and source code repositories. A developer working on one such Ansible project can seamlessly switch to another given a standard naming convention. Error Reduction: With improper naming there can be pitfalls.

Ansible Prerequisites Before jumping on to learning Ansible, have a firm grounding in Linux system administration and shell scripting. You can use Ansible for a lot of automation projects. The primary target audience for this blog post are DevOps engineers, IT infrastructure engineers and system administrators who create and manage IT infrastructure to run workloads. A good understanding of YAML is required before starting to write Ansible playbooks. A background in at least one programming language helps.

Architecture 1: Kubernetes Control Plane Without HA Create three Virtual Machine guests on your laptop or workstation. VM 01 - Kubernetes Control Plane VM 02, VM 03 - Kubernetes Worker nodes Architecture 2: Kubernetes Control Plane With HA Create five Virtual Machine guests on your laptop or workstation. VM 01, VM 02, VM 03 - Kubernetes Control Plane with HA VM 04, VM 05 - Kubernetes Worker nodes Use the Kubeadm tool to create the cluster.

A reference application is a sample application that is used as a guide for developers to learn and implement best practices for software development, testing, deployment, and operations within a specific technology stack or framework. It can serve as a blueprint for building and maintaining similar applications and can be used to demonstrate the use of tools, processes, and techniques for achieving high levels of automation, scalability, and reliability. If you are learning how to deploy applications to Kubernetes of Virtual Machines in cloud, create your own tiny application.

In the Kubernetes Objects Required For A Typical Web Application post we talked about few Kubernetes objects that a web application developer should get accustomed to. In this post, we will extend the series and talk about more objects that can help web developers scale their applications. As we delve deeper into Kubernetes topics, the demarcation of roles and skill sets start to reveal. In larger organizations, a dedicated team of infrastructure engineers design and make choices of network topology, IAC tooling and orchestration of the Kubernetes clusters and CI/CD pipelines.

In a previous post, we discussed using age to manage secrets in Git repositories. In this post, let’s improve our secrets management workflow in Git repositories using SOPS. sops is an editor of encrypted files that supports popular configuration formats such as YAML and various encryption techniques such as age. Read the blog post about age to install the package and creating the key file. This time, we will use sops to perform encryption and decryption operations instead of the age command.

KVM (Kernel-based Virtual Machine), libvirt, and QEMU are three components that work together to provide a virtualization solution on Linux systems. KVM is a virtualization infrastructure built into the Linux kernel that allows it to run multiple virtual machines (VMs) on a single physical host. It provides the underlying virtualization technology, such as hardware acceleration for virtualized CPU and memory, and device emulation. libvirt is an open-source API, daemon, and management tool for virtualization environments, it provides a common, stable, and simple interface for managing virtualization technologies such as KVM, QEMU, and others.

NFS Server To run your own NFS (Network File System) server, you’ll need to first install Linux on your server. I’d go with Debian, Ubuntu or CentOS distributions. Once you’ve done that, you can install the NFS server software, which is typically included with most Linux distributions. After the NFS server software is installed, you’ll need to configure it to specify which directories on the server should be shared with NFS clients, and what type of access they should have.

There are many applications and technologies enabled by VPN. We will focus on one of them in this post: client VPN. Connecting To A Private Network If the server you are trying to access is on a private network, you can use a VPN to connect to the network as if you were physically present on the same network. This can be useful if you need to access resources or devices that are only available on the private network.

syslog Syslog is a standard for logging system events on Unix and Linux systems. It is typically used to collect and store log messages from various applications and system components, such as the kernel, system libraries, and applications. Syslog uses a client-server model, where each client application sends log messages to a central syslog server, which then stores the messages in a log file. The syslog server can also forward the log messages to other syslog servers or send them to a log management system for further analysis.

There are many tools and software programs that can be used for monitoring and performance analysis on Linux systems. Some popular options include: top - This is a command-line utility that shows real-time information about the processes running on a Linux system, such as their CPU and memory usage. htop - This is a more advanced version of top that provides a more user-friendly interface and additional features, such as the ability to sort processes by different metrics and to kill processes.

To run your own email server using Linux and other open source software, you’ll need to first choose a Linux distribution and install it on your server. I’d go with either Ubuntu, Debian or Rocky Linux. Once you’ve done that, you can choose an email server software that is compatible with Linux, such as Postfix or Exim. After installing and configuring the email server software, you’ll need to set up DNS records and configure authentication and encryption to ensure that your email server is secure.

Definition A load balancer is a type of software or hardware that distributes incoming traffic across multiple servers or resources. This allows the load balancer to distribute the workload evenly, improving the performance and availability of the application. The Load Balancer Lab To run your own load balancer using open source software, you will need to: Install and configure the load balancer software on a server. Some popular open source options include HAProxy, Nginx, and Envoy.

Your web applications need a solution to store and retrieve its data. A relational database is often used in web applications. MySQL, MariaDB and PostgreSQL are some popular relational databases. There’s also SQLite. Many applications can use any of these relational databases by the virtue of the database layer abstraction. If you are writing your own web application, pick any one database and install it on your web server. Install The Database Install the package.

I see a lot of people are trying to break into software engineering and DevOps. There are many inspiring stories out there. People from other industries and verticals have switched to IT and are having a successful career. You can do it too. Let us look at the resources available to you. Online Vs. Offline Training And Learning Resources Online All you need to break into DevOps is: A laptop or a desktop computer Internet connectivity A quiet place Time Motivation that’s all.

Once upon a time, Apache was the de-facto web server solution. Later, Nginx became popular. If you are getting started with DevOps and Linux system administration, I would recommend you to start with Nginx. Start With A Static Website What is a static website? A website made from HTML and CSS. And maybe some JavaScript, images, videos, fonts, etc. The key takeaway is that there is no server side application involved.

Are you storing secrets such as database credentials, API keys, etc. unencrypted in Git repositories? Stop. To protect your secrets, do not store them anywhere unencrypted. Especially in Git repositories. Ideally, your organization must have some vault solution where secrets can be stored and securely shared with people on a need-to-know basis. In many small organizations, having such a central secrets management solution is still a luxury. The need to store such secret information in Git repositories is obvious.

From an application developer and Kubernetes user’s point of view, you have to have a working knowledge of Kubernetes. The post outlines the most important Kubernetes objects required to deploy a typical web application. Let us assume that the web application uses the two-tier architecture. We also assume that the cluster is created and administered by an infrastructure or DevOps engineer and the necessary access is provided to the developer to deploy their web application onto the Kubernetes cluster.

Introduction If you have chosen the DevOps engineering path for your career, Linux system administration skills are a must. Companies run their workloads on Linux on-premise as well as in the cloud. Many developers write software on their Linux laptops and workstations. In this post, I will lay out a plan to master Linux system administration skills. The journey begins with you becoming a Linux desktop user. Gradually, you start using your laptop as a Linux server.

Learn Linux. Install Linux on your laptop. Get familiar with Linux commands. Learn virtualization. Unlock the path to learn more Linux. Programming. Acquiring some programming skills using a general purpose programming language like Python goes a long way. Learning some web development is required in most DevOps engineering contexts. Although you don’t have to be an expert in web development, you should have a clear understanding of workloads consisting of web applications and microservices.

As soon as you are ready to deploy services and applications on the Internet, the first thing you need is a registered domain and a DNS server. Often people just use the DNS service provided by the domain registrar or the hosting or cloud provider. Using the managed service is not a requirement. You can host your own DNS server and manage the DNS for your domains. There are many open source software using which you can build your own DNS servers.

Introduction The Linux Kernel parameters are settings that can be configured to control the behavior of the Linux kernel. They are typically used to fine-tune system performance or to enable/disable certain features. Some examples of kernel parameters include: Memory-related parameters: These parameters control how the kernel manages system memory, including how much memory is allocated to user processes and how aggressively the kernel caches data. Processor-related parameters: These parameters control how the kernel interacts with the system’s processors, including how it schedules processes and how it handles interrupts.

If you are wondering how to automate the installation and configuration of Jenkins using code, this post is for you. Jenkins is a popular open source tool to build CI/CD pipelines. Ansible is a popular open source tool to automate a lot of things in IT, including CI/CD and infrastructure orchestration. Ansible can be used to deploy applications in the cloud. Ansible is a nice tool to execute steps such as:

The blog post attempts to answer some questions like: How to become a DevOps engineer? How to prepare for a DevOps engineer interview? How to get a DevOps engineer job? In a previous blog post, I wrote about the path an aspiring DevOps engineer could follow. In this blog post, I will lay out a concrete plan using which you can prepare yourself for a DevOps engineer job. If you follow the steps carefully, you will be armed with practical DevOps knowledge, and you will be able to apply for DevOps engineer jobs confidently.

The build and deploy engineer is a role in IT/infrastructure/devops teams of organizations that is responsible for deploying a set of applications using CI/CD pipelines. Usually, they use the pipelines, tools and processes created by DevOps engineers, consultants or practitioners. They tweak things with tools like Ansible, Jenkins, Git, Maven, etc. here and there a bit. Are you one such build and deploy engineer looking to transition your career into DevOps engineering?

The Tech Chorus blog by Sudheer Satyanarayana started way back in 2008. The blog has used various hosting technologies and software over the years. Initially, the blog site used Drupal content management system. LAMP was a popular technology stack those days. Drupal was one of my favorite CMSes back then. The Drupal site was hosted on a cPanel server. As life progressed, there was not enough time to patch Drupal and its plugins.

Introduction The article explains how to run your own OpenVPN server. We will create a Certificate Authority Server and an OpenVPN server. We will also generate certificates for the clients. We will also learn how to manage revocation of client certificates using the Ansible roles. Use the Ansible roles gavika.openvpn and gavika.easy_rsa to install and configure your OpenVPN server. You can install the OpenVPN server on any public cloud or hosting provider or on-premise servers.

Install the Ansible role gavika.aws_cloudwatchagent via Galaxy ansible-galaxy install gavika.aws_cloudwatchagent Create The Playbook File - cw-play.yml : --- - hosts: all become: true vars: roles: - role: gavika.aws_cloudwatchagent Prepare the AWS CloudWatch Agent configuration In your variables file, use aws_cloudwatch_agent_config agent: metrics_collection_interval: 60 run_as_user: "cwagent" metrics: namespace: "Gavika" append_dimensions: InstanceId: "${aws:InstanceId}" metrics_collected: disk: measurement: - used_percent metrics_collection_interval: 60 resources: - "*" mem: measurement: - mem_used_percent metrics_collection_interval: 60 In this example, I am using the namespace, Gavika.

Install PostgreSQL Server Fedora and CentOS: sudo dnf install postgresql-server Ubuntu 18.04: sudo apt install postgresql New Server Initialization On CentOS 7/Fedora 30: sudo postgresql-setup initdb Upgrading From An Older Version sudo postgresql-setup --upgrade Administering The Database Server Managing The postgresql Daemon Starting PostgreSQL server sudo systemctl start postgresql Checking PostgreSQL Server Status: sudo systemctl status postgresql Enabling PostgreSQL Server Systemd Unit/Enabling PostgreSQL Server On Boot: sudo systemctl enable postgresql Allowing Password Based Login From localhost Edit /var/lib/pgsql/data/pg_hba.

In a previous series of blog posts, we discussed the Kubernetes objects typically used to run a web application. We covered, Namespace, Pod, ConfigMap, Secret, Service, Deployment, ServiceAccount, Ingress, PDB, HPA, PV, PVC, Job and CronJob. In this post, we will discuss some fundamental building blocks for the Kubernetes cluster administration: RBAC objects. In most situations, Kubernetes API server is started with the flag --authorization-mode=RBAC which enables RBAC in the cluster.

Purpose Of Having Naming Conventions For An Ansible Project Consistency: Adopting a naming convention standardizes naming across the project and organization. This makes it easier for developers to switch between projects. Typically, an organization with an infrastructure team will have several Ansible projects and source code repositories. A developer working on one such Ansible project can seamlessly switch to another given a standard naming convention. Error Reduction: With improper naming there can be pitfalls.

Architecture 1: Kubernetes Control Plane Without HA Create three Virtual Machine guests on your laptop or workstation. VM 01 - Kubernetes Control Plane VM 02, VM 03 - Kubernetes Worker nodes Architecture 2: Kubernetes Control Plane With HA Create five Virtual Machine guests on your laptop or workstation. VM 01, VM 02, VM 03 - Kubernetes Control Plane with HA VM 04, VM 05 - Kubernetes Worker nodes Use the Kubeadm tool to create the cluster.

In the Kubernetes Objects Required For A Typical Web Application post we talked about few Kubernetes objects that a web application developer should get accustomed to. In this post, we will extend the series and talk about more objects that can help web developers scale their applications. As we delve deeper into Kubernetes topics, the demarcation of roles and skill sets start to reveal. In larger organizations, a dedicated team of infrastructure engineers design and make choices of network topology, IAC tooling and orchestration of the Kubernetes clusters and CI/CD pipelines.

In a previous post, we discussed using age to manage secrets in Git repositories. In this post, let’s improve our secrets management workflow in Git repositories using SOPS. sops is an editor of encrypted files that supports popular configuration formats such as YAML and various encryption techniques such as age. Read the blog post about age to install the package and creating the key file. This time, we will use sops to perform encryption and decryption operations instead of the age command.

There are many applications and technologies enabled by VPN. We will focus on one of them in this post: client VPN. Connecting To A Private Network If the server you are trying to access is on a private network, you can use a VPN to connect to the network as if you were physically present on the same network. This can be useful if you need to access resources or devices that are only available on the private network.

Once upon a time, Apache was the de-facto web server solution. Later, Nginx became popular. If you are getting started with DevOps and Linux system administration, I would recommend you to start with Nginx. Start With A Static Website What is a static website? A website made from HTML and CSS. And maybe some JavaScript, images, videos, fonts, etc. The key takeaway is that there is no server side application involved.

Are you storing secrets such as database credentials, API keys, etc. unencrypted in Git repositories? Stop. To protect your secrets, do not store them anywhere unencrypted. Especially in Git repositories. Ideally, your organization must have some vault solution where secrets can be stored and securely shared with people on a need-to-know basis. In many small organizations, having such a central secrets management solution is still a luxury. The need to store such secret information in Git repositories is obvious.

Introduction If you have chosen the DevOps engineering path for your career, Linux system administration skills are a must. Companies run their workloads on Linux on-premise as well as in the cloud. Many developers write software on their Linux laptops and workstations. In this post, I will lay out a plan to master Linux system administration skills. The journey begins with you becoming a Linux desktop user. Gradually, you start using your laptop as a Linux server.

In a previous series of blog posts, we discussed the Kubernetes objects typically used to run a web application. We covered, Namespace, Pod, ConfigMap, Secret, Service, Deployment, ServiceAccount, Ingress, PDB, HPA, PV, PVC, Job and CronJob. In this post, we will discuss some fundamental building blocks for the Kubernetes cluster administration: RBAC objects. In most situations, Kubernetes API server is started with the flag --authorization-mode=RBAC which enables RBAC in the cluster.

This is a guide to write a Kubernetes controller. We will kick off by inspecting the Kubernetes API from inside a pod within the cluster. Minikube suffices for this exercise. But you can conduct the exercise to any Kubernetes cluster. The controller watches events related to Kubernetes pods using the Kubernetes API. When there is a new event, the controller logs the event’s type and the name of the affected pod.

Architecture 1: Kubernetes Control Plane Without HA Create three Virtual Machine guests on your laptop or workstation. VM 01 - Kubernetes Control Plane VM 02, VM 03 - Kubernetes Worker nodes Architecture 2: Kubernetes Control Plane With HA Create five Virtual Machine guests on your laptop or workstation. VM 01, VM 02, VM 03 - Kubernetes Control Plane with HA VM 04, VM 05 - Kubernetes Worker nodes Use the Kubeadm tool to create the cluster.

In the Kubernetes Objects Required For A Typical Web Application post we talked about few Kubernetes objects that a web application developer should get accustomed to. In this post, we will extend the series and talk about more objects that can help web developers scale their applications. As we delve deeper into Kubernetes topics, the demarcation of roles and skill sets start to reveal. In larger organizations, a dedicated team of infrastructure engineers design and make choices of network topology, IAC tooling and orchestration of the Kubernetes clusters and CI/CD pipelines.

In a previous post, we discussed using age to manage secrets in Git repositories. In this post, let’s improve our secrets management workflow in Git repositories using SOPS. sops is an editor of encrypted files that supports popular configuration formats such as YAML and various encryption techniques such as age. Read the blog post about age to install the package and creating the key file. This time, we will use sops to perform encryption and decryption operations instead of the age command.

Are you storing secrets such as database credentials, API keys, etc. unencrypted in Git repositories? Stop. To protect your secrets, do not store them anywhere unencrypted. Especially in Git repositories. Ideally, your organization must have some vault solution where secrets can be stored and securely shared with people on a need-to-know basis. In many small organizations, having such a central secrets management solution is still a luxury. The need to store such secret information in Git repositories is obvious.

From an application developer and Kubernetes user’s point of view, you have to have a working knowledge of Kubernetes. The post outlines the most important Kubernetes objects required to deploy a typical web application. Let us assume that the web application uses the two-tier architecture. We also assume that the cluster is created and administered by an infrastructure or DevOps engineer and the necessary access is provided to the developer to deploy their web application onto the Kubernetes cluster.

In a previous series of blog posts, we discussed the Kubernetes objects typically used to run a web application. We covered, Namespace, Pod, ConfigMap, Secret, Service, Deployment, ServiceAccount, Ingress, PDB, HPA, PV, PVC, Job and CronJob. In this post, we will discuss some fundamental building blocks for the Kubernetes cluster administration: RBAC objects. In most situations, Kubernetes API server is started with the flag --authorization-mode=RBAC which enables RBAC in the cluster.

Introduction We have the host machine with the OS Ubuntu 22.04. On this PC or server, we will create two virtual machine guests: myubuntu2204test01 having static IP of 192.168.122.146 myubuntu2204test02 having static IP of 192.168.122.147 The guest VMs will use the default network created by libvirt. The gateway IP for the default network is 192.168.122.1. We will achieve automation using libvirt, qemu and cloud-init. To go through the article and exercise, you should have a rudimentary understanding of Linux system administration and networking.

So, you have an SSH key pair. The public key has been added on to the server. On the client, ie your laptop/desktop you have your private key. For some reason, your private key has not been loaded into memory. All you have to do is start the ssh-agent and then load the key into memory via ssh-add. Step 1: Start the agent eval $(ssh-agent) Step 2: load the key into memory

Using Linux KVM, Expose Virtual Guests On The LAN Audience: The blog post is for beginner to intermediary Linux system administrators. You should have a thorough understanding of the shell commands and be comfortable on the command line be able to install and configure packages, etc. be able to start and stop services using systemd be familiar with Linux configuration files be able to set Linux kernel parameters using sysctl be able to enable and disable Kernel modules be comfortable installing and using guest VMs using libvirt You should have a rudimentary understanding of networking concepts and tooling such as

Ansible Prerequisites Before jumping on to learning Ansible, have a firm grounding in Linux system administration and shell scripting. You can use Ansible for a lot of automation projects. The primary target audience for this blog post are DevOps engineers, IT infrastructure engineers and system administrators who create and manage IT infrastructure to run workloads. A good understanding of YAML is required before starting to write Ansible playbooks. A background in at least one programming language helps.

Architecture 1: Kubernetes Control Plane Without HA Create three Virtual Machine guests on your laptop or workstation. VM 01 - Kubernetes Control Plane VM 02, VM 03 - Kubernetes Worker nodes Architecture 2: Kubernetes Control Plane With HA Create five Virtual Machine guests on your laptop or workstation. VM 01, VM 02, VM 03 - Kubernetes Control Plane with HA VM 04, VM 05 - Kubernetes Worker nodes Use the Kubeadm tool to create the cluster.

KVM (Kernel-based Virtual Machine), libvirt, and QEMU are three components that work together to provide a virtualization solution on Linux systems. KVM is a virtualization infrastructure built into the Linux kernel that allows it to run multiple virtual machines (VMs) on a single physical host. It provides the underlying virtualization technology, such as hardware acceleration for virtualized CPU and memory, and device emulation. libvirt is an open-source API, daemon, and management tool for virtualization environments, it provides a common, stable, and simple interface for managing virtualization technologies such as KVM, QEMU, and others.

Introduction If you have chosen the DevOps engineering path for your career, Linux system administration skills are a must. Companies run their workloads on Linux on-premise as well as in the cloud. Many developers write software on their Linux laptops and workstations. In this post, I will lay out a plan to master Linux system administration skills. The journey begins with you becoming a Linux desktop user. Gradually, you start using your laptop as a Linux server.

Learn Linux. Install Linux on your laptop. Get familiar with Linux commands. Learn virtualization. Unlock the path to learn more Linux. Programming. Acquiring some programming skills using a general purpose programming language like Python goes a long way. Learning some web development is required in most DevOps engineering contexts. Although you don’t have to be an expert in web development, you should have a clear understanding of workloads consisting of web applications and microservices.

Introduction The Linux Kernel parameters are settings that can be configured to control the behavior of the Linux kernel. They are typically used to fine-tune system performance or to enable/disable certain features. Some examples of kernel parameters include: Memory-related parameters: These parameters control how the kernel manages system memory, including how much memory is allocated to user processes and how aggressively the kernel caches data. Processor-related parameters: These parameters control how the kernel interacts with the system’s processors, including how it schedules processes and how it handles interrupts.

The blog post attempts to answer some questions like: How to become a DevOps engineer? How to prepare for a DevOps engineer interview? How to get a DevOps engineer job? In a previous blog post, I wrote about the path an aspiring DevOps engineer could follow. In this blog post, I will lay out a concrete plan using which you can prepare yourself for a DevOps engineer job. If you follow the steps carefully, you will be armed with practical DevOps knowledge, and you will be able to apply for DevOps engineer jobs confidently.

The Tech Chorus blog by Sudheer Satyanarayana started way back in 2008. The blog has used various hosting technologies and software over the years. Initially, the blog site used Drupal content management system. LAMP was a popular technology stack those days. Drupal was one of my favorite CMSes back then. The Drupal site was hosted on a cPanel server. As life progressed, there was not enough time to patch Drupal and its plugins.

What is SSH Key Management? The blog post is intended towards someone new to SSH key management. Do you have just one SSH key pair? Do you have multiple key pairs? What are some pros and cons of having single or multiple key pairs? The post answers such questions about SSH key usage in practice. The Premise So, someone walked up to you or in a video call asked for your SSH public key?

Introduction The article explains how to run your own OpenVPN server. We will create a Certificate Authority Server and an OpenVPN server. We will also generate certificates for the clients. We will also learn how to manage revocation of client certificates using the Ansible roles. Use the Ansible roles gavika.openvpn and gavika.easy_rsa to install and configure your OpenVPN server. You can install the OpenVPN server on any public cloud or hosting provider or on-premise servers.

Install PostgreSQL Server Fedora and CentOS: sudo dnf install postgresql-server Ubuntu 18.04: sudo apt install postgresql New Server Initialization On CentOS 7/Fedora 30: sudo postgresql-setup initdb Upgrading From An Older Version sudo postgresql-setup --upgrade Administering The Database Server Managing The postgresql Daemon Starting PostgreSQL server sudo systemctl start postgresql Checking PostgreSQL Server Status: sudo systemctl status postgresql Enabling PostgreSQL Server Systemd Unit/Enabling PostgreSQL Server On Boot: sudo systemctl enable postgresql Allowing Password Based Login From localhost Edit /var/lib/pgsql/data/pg_hba.

Introduction We have the host machine with the OS Ubuntu 22.04. On this PC or server, we will create two virtual machine guests: myubuntu2204test01 having static IP of 192.168.122.146 myubuntu2204test02 having static IP of 192.168.122.147 The guest VMs will use the default network created by libvirt. The gateway IP for the default network is 192.168.122.1. We will achieve automation using libvirt, qemu and cloud-init. To go through the article and exercise, you should have a rudimentary understanding of Linux system administration and networking.

Using Linux KVM, Expose Virtual Guests On The LAN Audience: The blog post is for beginner to intermediary Linux system administrators. You should have a thorough understanding of the shell commands and be comfortable on the command line be able to install and configure packages, etc. be able to start and stop services using systemd be familiar with Linux configuration files be able to set Linux kernel parameters using sysctl be able to enable and disable Kernel modules be comfortable installing and using guest VMs using libvirt You should have a rudimentary understanding of networking concepts and tooling such as

KVM (Kernel-based Virtual Machine), libvirt, and QEMU are three components that work together to provide a virtualization solution on Linux systems. KVM is a virtualization infrastructure built into the Linux kernel that allows it to run multiple virtual machines (VMs) on a single physical host. It provides the underlying virtualization technology, such as hardware acceleration for virtualized CPU and memory, and device emulation. libvirt is an open-source API, daemon, and management tool for virtualization environments, it provides a common, stable, and simple interface for managing virtualization technologies such as KVM, QEMU, and others.

Introduction We have the host machine with the OS Ubuntu 22.04. On this PC or server, we will create two virtual machine guests: myubuntu2204test01 having static IP of 192.168.122.146 myubuntu2204test02 having static IP of 192.168.122.147 The guest VMs will use the default network created by libvirt. The gateway IP for the default network is 192.168.122.1. We will achieve automation using libvirt, qemu and cloud-init. To go through the article and exercise, you should have a rudimentary understanding of Linux system administration and networking.

So, you have an SSH key pair. The public key has been added on to the server. On the client, ie your laptop/desktop you have your private key. For some reason, your private key has not been loaded into memory. All you have to do is start the ssh-agent and then load the key into memory via ssh-add. Step 1: Start the agent eval $(ssh-agent) Step 2: load the key into memory

Using Linux KVM, Expose Virtual Guests On The LAN Audience: The blog post is for beginner to intermediary Linux system administrators. You should have a thorough understanding of the shell commands and be comfortable on the command line be able to install and configure packages, etc. be able to start and stop services using systemd be familiar with Linux configuration files be able to set Linux kernel parameters using sysctl be able to enable and disable Kernel modules be comfortable installing and using guest VMs using libvirt You should have a rudimentary understanding of networking concepts and tooling such as

Ansible Prerequisites Before jumping on to learning Ansible, have a firm grounding in Linux system administration and shell scripting. You can use Ansible for a lot of automation projects. The primary target audience for this blog post are DevOps engineers, IT infrastructure engineers and system administrators who create and manage IT infrastructure to run workloads. A good understanding of YAML is required before starting to write Ansible playbooks. A background in at least one programming language helps.

KVM (Kernel-based Virtual Machine), libvirt, and QEMU are three components that work together to provide a virtualization solution on Linux systems. KVM is a virtualization infrastructure built into the Linux kernel that allows it to run multiple virtual machines (VMs) on a single physical host. It provides the underlying virtualization technology, such as hardware acceleration for virtualized CPU and memory, and device emulation. libvirt is an open-source API, daemon, and management tool for virtualization environments, it provides a common, stable, and simple interface for managing virtualization technologies such as KVM, QEMU, and others.

NFS Server To run your own NFS (Network File System) server, you’ll need to first install Linux on your server. I’d go with Debian, Ubuntu or CentOS distributions. Once you’ve done that, you can install the NFS server software, which is typically included with most Linux distributions. After the NFS server software is installed, you’ll need to configure it to specify which directories on the server should be shared with NFS clients, and what type of access they should have.

syslog Syslog is a standard for logging system events on Unix and Linux systems. It is typically used to collect and store log messages from various applications and system components, such as the kernel, system libraries, and applications. Syslog uses a client-server model, where each client application sends log messages to a central syslog server, which then stores the messages in a log file. The syslog server can also forward the log messages to other syslog servers or send them to a log management system for further analysis.

There are many tools and software programs that can be used for monitoring and performance analysis on Linux systems. Some popular options include: top - This is a command-line utility that shows real-time information about the processes running on a Linux system, such as their CPU and memory usage. htop - This is a more advanced version of top that provides a more user-friendly interface and additional features, such as the ability to sort processes by different metrics and to kill processes.

Introduction If you have chosen the DevOps engineering path for your career, Linux system administration skills are a must. Companies run their workloads on Linux on-premise as well as in the cloud. Many developers write software on their Linux laptops and workstations. In this post, I will lay out a plan to master Linux system administration skills. The journey begins with you becoming a Linux desktop user. Gradually, you start using your laptop as a Linux server.

Introduction The Linux Kernel parameters are settings that can be configured to control the behavior of the Linux kernel. They are typically used to fine-tune system performance or to enable/disable certain features. Some examples of kernel parameters include: Memory-related parameters: These parameters control how the kernel manages system memory, including how much memory is allocated to user processes and how aggressively the kernel caches data. Processor-related parameters: These parameters control how the kernel interacts with the system’s processors, including how it schedules processes and how it handles interrupts.

Using Git with SSH is a common practice among software developers. The convenience of not having to remember passwords is a huge productivity boost in software development workflows. In a previous blog post, I wrote about managing SSH keys. Having many SSH keys can cause few issues: ssh-agent doesn’t work well with too many keys. Can’t always map SSH keys to servers in SSH client configuration. Both personal and company projects Git can be hosted on the same server or third-party service such as Github.

What is SSH Key Management? The blog post is intended towards someone new to SSH key management. Do you have just one SSH key pair? Do you have multiple key pairs? What are some pros and cons of having single or multiple key pairs? The post answers such questions about SSH key usage in practice. The Premise So, someone walked up to you or in a video call asked for your SSH public key?

Introduction The article explains how to run your own OpenVPN server. We will create a Certificate Authority Server and an OpenVPN server. We will also generate certificates for the clients. We will also learn how to manage revocation of client certificates using the Ansible roles. Use the Ansible roles gavika.openvpn and gavika.easy_rsa to install and configure your OpenVPN server. You can install the OpenVPN server on any public cloud or hosting provider or on-premise servers.

We are pleased to announce gavika.administrators. The Ansible role provides a declarative method to create Linux user accounts with administrative privileges. In other words, these users have sudo access without password and are empowered to run all commands on the system. You might be wondering why you would need a role when you can write a couple tasks yourselves in an Ansible playbook. The reason is, Do Not Repeat Yourself(DRY). Instead of writing such tasks over and over, use the abstraction provided by the role.

Yesterday, we announced the launch of Ansible role to install and configure AWS CloudWatch Agent. You might have seen my other open source Ansible roles on Ansible Galaxy and Github. In the same spirit, the company, Gavika Information Technologies Pvt. Ltd. Bangalore, has started publishing open source projects on Github. Ansible role to install and configure AWS CloudWatch Agent is the first project. Expect more projects in the future. These are some guidelines for the Ansible role projects that Gavika follows:

Ansible comes with a vault feature. It is meant to be used in the context of configuration management. But you can also use it as a standalone simple password vault for your personal or organization’s use. Initial setup of password vault: Create or clone a Git or another SCM repository git init Create the password vault ansible-vault create myvault.secret Type the new master password and confirm, ansible-vault will open your text editor.

In this tutorial, I will provide step-by-step process to implement MySQL replication. We will create one master and one slave. We will use two CentOS 6 servers - one for master and the other for slave. This following steps have been tested on two virtual machines. Our master server will have IP address 192.168.122.10. Our slave server will have IP address 192.168.122.12. You might want to run SELinux in permissive mode.

Moving around You can use the arrow keys on keyboard to move around in the command line. Bash also provides convenient keyboard shortcuts to navigate effectively. Try them out and see for yourself. To become a Bash pro user you have to get yourself familiar with the keyboard shortcuts. Once you do, you’ll find yourself productive. Shortcut Description CTRL+b move backward one character CTRL+f move forward one character ESC+b move one word backward ESC+f move one word forward CTRL+a move to beginning of line CTRL+e move to end of line CTRL+p move to previous line CTRL+n move to next line ESC+< move to first line of history list ESC+> move to last line of history list Moving around words using ESC+f and ESC+b are my favourites in this list.

Introduction We have the host machine with the OS Ubuntu 22.04. On this PC or server, we will create two virtual machine guests: myubuntu2204test01 having static IP of 192.168.122.146 myubuntu2204test02 having static IP of 192.168.122.147 The guest VMs will use the default network created by libvirt. The gateway IP for the default network is 192.168.122.1. We will achieve automation using libvirt, qemu and cloud-init. To go through the article and exercise, you should have a rudimentary understanding of Linux system administration and networking.

Using Linux KVM, Expose Virtual Guests On The LAN Audience: The blog post is for beginner to intermediary Linux system administrators. You should have a thorough understanding of the shell commands and be comfortable on the command line be able to install and configure packages, etc. be able to start and stop services using systemd be familiar with Linux configuration files be able to set Linux kernel parameters using sysctl be able to enable and disable Kernel modules be comfortable installing and using guest VMs using libvirt You should have a rudimentary understanding of networking concepts and tooling such as

KVM (Kernel-based Virtual Machine), libvirt, and QEMU are three components that work together to provide a virtualization solution on Linux systems. KVM is a virtualization infrastructure built into the Linux kernel that allows it to run multiple virtual machines (VMs) on a single physical host. It provides the underlying virtualization technology, such as hardware acceleration for virtualized CPU and memory, and device emulation. libvirt is an open-source API, daemon, and management tool for virtualization environments, it provides a common, stable, and simple interface for managing virtualization technologies such as KVM, QEMU, and others.

This is a guide to write a Kubernetes controller. We will kick off by inspecting the Kubernetes API from inside a pod within the cluster. Minikube suffices for this exercise. But you can conduct the exercise to any Kubernetes cluster. The controller watches events related to Kubernetes pods using the Kubernetes API. When there is a new event, the controller logs the event’s type and the name of the affected pod.

This is a guide to write a Kubernetes controller. We will kick off by inspecting the Kubernetes API from inside a pod within the cluster. Minikube suffices for this exercise. But you can conduct the exercise to any Kubernetes cluster. The controller watches events related to Kubernetes pods using the Kubernetes API. When there is a new event, the controller logs the event’s type and the name of the affected pod.

This is a guide to write a Kubernetes controller. We will kick off by inspecting the Kubernetes API from inside a pod within the cluster. Minikube suffices for this exercise. But you can conduct the exercise to any Kubernetes cluster. The controller watches events related to Kubernetes pods using the Kubernetes API. When there is a new event, the controller logs the event’s type and the name of the affected pod.

This is a guide to write a Kubernetes controller. We will kick off by inspecting the Kubernetes API from inside a pod within the cluster. Minikube suffices for this exercise. But you can conduct the exercise to any Kubernetes cluster. The controller watches events related to Kubernetes pods using the Kubernetes API. When there is a new event, the controller logs the event’s type and the name of the affected pod.

In this blog post, I will explain how I implemented a graph algorithm to solve the database migration problem in an application pluggable module system. Prerequisites: Working knowledge of Python Working knowledge of Graph Theory. Familiar with the terms: Edge, vertex, path, sink, source, digraph, path graph, etc. Gavika Web Framework has a pluggable module system. The modules can be developed independently. They can be installed, upgraded and removed from the main application.

You access Python dictionary keys using the syntax: my_dicy[my_key] For example: >>> my_dict = {'food': 'idly'} >>> my_dict['food'] 'idly' Sometimes, you might want to access the dictionary keys using: my_dict.my_key syntax. If you do this is what happens: >>> my_dict.food Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'dict' object has no attribute 'food' How can you solve this? Easy. pip install attrdict How do you use the newly installed package?

So, you have an SSH key pair. The public key has been added on to the server. On the client, ie your laptop/desktop you have your private key. For some reason, your private key has not been loaded into memory. All you have to do is start the ssh-agent and then load the key into memory via ssh-add. Step 1: Start the agent eval $(ssh-agent) Step 2: load the key into memory

What is SSH Key Management? The blog post is intended towards someone new to SSH key management. Do you have just one SSH key pair? Do you have multiple key pairs? What are some pros and cons of having single or multiple key pairs? The post answers such questions about SSH key usage in practice. The Premise So, someone walked up to you or in a video call asked for your SSH public key?

So, you have an SSH key pair. The public key has been added on to the server. On the client, ie your laptop/desktop you have your private key. For some reason, your private key has not been loaded into memory. All you have to do is start the ssh-agent and then load the key into memory via ssh-add. Step 1: Start the agent eval $(ssh-agent) Step 2: load the key into memory

Using Git with SSH is a common practice among software developers. The convenience of not having to remember passwords is a huge productivity boost in software development workflows. In a previous blog post, I wrote about managing SSH keys. Having many SSH keys can cause few issues: ssh-agent doesn’t work well with too many keys. Can’t always map SSH keys to servers in SSH client configuration. Both personal and company projects Git can be hosted on the same server or third-party service such as Github.

What is SSH Key Management? The blog post is intended towards someone new to SSH key management. Do you have just one SSH key pair? Do you have multiple key pairs? What are some pros and cons of having single or multiple key pairs? The post answers such questions about SSH key usage in practice. The Premise So, someone walked up to you or in a video call asked for your SSH public key?

Using Linux KVM, Expose Virtual Guests On The LAN Audience: The blog post is for beginner to intermediary Linux system administrators. You should have a thorough understanding of the shell commands and be comfortable on the command line be able to install and configure packages, etc. be able to start and stop services using systemd be familiar with Linux configuration files be able to set Linux kernel parameters using sysctl be able to enable and disable Kernel modules be comfortable installing and using guest VMs using libvirt You should have a rudimentary understanding of networking concepts and tooling such as

KVM (Kernel-based Virtual Machine), libvirt, and QEMU are three components that work together to provide a virtualization solution on Linux systems. KVM is a virtualization infrastructure built into the Linux kernel that allows it to run multiple virtual machines (VMs) on a single physical host. It provides the underlying virtualization technology, such as hardware acceleration for virtualized CPU and memory, and device emulation. libvirt is an open-source API, daemon, and management tool for virtualization environments, it provides a common, stable, and simple interface for managing virtualization technologies such as KVM, QEMU, and others.

Purpose Of Having Naming Conventions For An Ansible Project Consistency: Adopting a naming convention standardizes naming across the project and organization. This makes it easier for developers to switch between projects. Typically, an organization with an infrastructure team will have several Ansible projects and source code repositories. A developer working on one such Ansible project can seamlessly switch to another given a standard naming convention. Error Reduction: With improper naming there can be pitfalls.

Ansible Prerequisites Before jumping on to learning Ansible, have a firm grounding in Linux system administration and shell scripting. You can use Ansible for a lot of automation projects. The primary target audience for this blog post are DevOps engineers, IT infrastructure engineers and system administrators who create and manage IT infrastructure to run workloads. A good understanding of YAML is required before starting to write Ansible playbooks. A background in at least one programming language helps.

Introduction The Linux Kernel parameters are settings that can be configured to control the behavior of the Linux kernel. They are typically used to fine-tune system performance or to enable/disable certain features. Some examples of kernel parameters include: Memory-related parameters: These parameters control how the kernel manages system memory, including how much memory is allocated to user processes and how aggressively the kernel caches data. Processor-related parameters: These parameters control how the kernel interacts with the system’s processors, including how it schedules processes and how it handles interrupts.

If you are wondering how to automate the installation and configuration of Jenkins using code, this post is for you. Jenkins is a popular open source tool to build CI/CD pipelines. Ansible is a popular open source tool to automate a lot of things in IT, including CI/CD and infrastructure orchestration. Ansible can be used to deploy applications in the cloud. Ansible is a nice tool to execute steps such as:

This is a blog post in IAC with Terraform series. IAC stands for Infrastructure As Code. Modern IT infrastructure can be orchestrated using programmatic methods. Terraform is(was?) a popular open source software used to orchestrate infrastructure in the cloud and elsewhere too. Terraform has the concept of modules. With modules, you can code abstract infrastructure. For example, if you are creating a pattern of infrastructure over and over again, you could abstract the pattern into a Terraform module.

Introduction The article explains how to run your own OpenVPN server. We will create a Certificate Authority Server and an OpenVPN server. We will also generate certificates for the clients. We will also learn how to manage revocation of client certificates using the Ansible roles. Use the Ansible roles gavika.openvpn and gavika.easy_rsa to install and configure your OpenVPN server. You can install the OpenVPN server on any public cloud or hosting provider or on-premise servers.

We are pleased to announce gavika.administrators. The Ansible role provides a declarative method to create Linux user accounts with administrative privileges. In other words, these users have sudo access without password and are empowered to run all commands on the system. You might be wondering why you would need a role when you can write a couple tasks yourselves in an Ansible playbook. The reason is, Do Not Repeat Yourself(DRY). Instead of writing such tasks over and over, use the abstraction provided by the role.

Short answer: use ipify ipify provides a simple public address API. Using the tool, you can determine your public IP address programmatically. If you are using the shell: curl 'https://api.ipify.org' Using it in a shell script: my_ip=$(curl 'https://api.ipify.org' -s) echo $my_ip Using the Ansible ipify module: - hosts: localhost vars: tasks: - name: Get my public IP ipify_facts: timeout: 20 delegate_to: localhost register: public_ip - name: output debug: msg="{{ ipify_public_ip }}" Sample output of Ansible playbook execution:

Yesterday, we announced the launch of Ansible role to install and configure AWS CloudWatch Agent. You might have seen my other open source Ansible roles on Ansible Galaxy and Github. In the same spirit, the company, Gavika Information Technologies Pvt. Ltd. Bangalore, has started publishing open source projects on Github. Ansible role to install and configure AWS CloudWatch Agent is the first project. Expect more projects in the future. These are some guidelines for the Ansible role projects that Gavika follows:

Install the Ansible role gavika.aws_cloudwatchagent via Galaxy ansible-galaxy install gavika.aws_cloudwatchagent Create The Playbook File - cw-play.yml : --- - hosts: all become: true vars: roles: - role: gavika.aws_cloudwatchagent Prepare the AWS CloudWatch Agent configuration In your variables file, use aws_cloudwatch_agent_config agent: metrics_collection_interval: 60 run_as_user: "cwagent" metrics: namespace: "Gavika" append_dimensions: InstanceId: "${aws:InstanceId}" metrics_collected: disk: measurement: - used_percent metrics_collection_interval: 60 resources: - "*" mem: measurement: - mem_used_percent metrics_collection_interval: 60 In this example, I am using the namespace, Gavika.

Ansible comes with a vault feature. It is meant to be used in the context of configuration management. But you can also use it as a standalone simple password vault for your personal or organization’s use. Initial setup of password vault: Create or clone a Git or another SCM repository git init Create the password vault ansible-vault create myvault.secret Type the new master password and confirm, ansible-vault will open your text editor.

A reference application is a sample application that is used as a guide for developers to learn and implement best practices for software development, testing, deployment, and operations within a specific technology stack or framework. It can serve as a blueprint for building and maintaining similar applications and can be used to demonstrate the use of tools, processes, and techniques for achieving high levels of automation, scalability, and reliability. If you are learning how to deploy applications to Kubernetes of Virtual Machines in cloud, create your own tiny application.

NFS Server To run your own NFS (Network File System) server, you’ll need to first install Linux on your server. I’d go with Debian, Ubuntu or CentOS distributions. Once you’ve done that, you can install the NFS server software, which is typically included with most Linux distributions. After the NFS server software is installed, you’ll need to configure it to specify which directories on the server should be shared with NFS clients, and what type of access they should have.

syslog Syslog is a standard for logging system events on Unix and Linux systems. It is typically used to collect and store log messages from various applications and system components, such as the kernel, system libraries, and applications. Syslog uses a client-server model, where each client application sends log messages to a central syslog server, which then stores the messages in a log file. The syslog server can also forward the log messages to other syslog servers or send them to a log management system for further analysis.

There are many tools and software programs that can be used for monitoring and performance analysis on Linux systems. Some popular options include: top - This is a command-line utility that shows real-time information about the processes running on a Linux system, such as their CPU and memory usage. htop - This is a more advanced version of top that provides a more user-friendly interface and additional features, such as the ability to sort processes by different metrics and to kill processes.

To run your own email server using Linux and other open source software, you’ll need to first choose a Linux distribution and install it on your server. I’d go with either Ubuntu, Debian or Rocky Linux. Once you’ve done that, you can choose an email server software that is compatible with Linux, such as Postfix or Exim. After installing and configuring the email server software, you’ll need to set up DNS records and configure authentication and encryption to ensure that your email server is secure.

Definition A load balancer is a type of software or hardware that distributes incoming traffic across multiple servers or resources. This allows the load balancer to distribute the workload evenly, improving the performance and availability of the application. The Load Balancer Lab To run your own load balancer using open source software, you will need to: Install and configure the load balancer software on a server. Some popular open source options include HAProxy, Nginx, and Envoy.

Your web applications need a solution to store and retrieve its data. A relational database is often used in web applications. MySQL, MariaDB and PostgreSQL are some popular relational databases. There’s also SQLite. Many applications can use any of these relational databases by the virtue of the database layer abstraction. If you are writing your own web application, pick any one database and install it on your web server. Install The Database Install the package.

As soon as you are ready to deploy services and applications on the Internet, the first thing you need is a registered domain and a DNS server. Often people just use the DNS service provided by the domain registrar or the hosting or cloud provider. Using the managed service is not a requirement. You can host your own DNS server and manage the DNS for your domains. There are many open source software using which you can build your own DNS servers.

A reference application is a sample application that is used as a guide for developers to learn and implement best practices for software development, testing, deployment, and operations within a specific technology stack or framework. It can serve as a blueprint for building and maintaining similar applications and can be used to demonstrate the use of tools, processes, and techniques for achieving high levels of automation, scalability, and reliability. If you are learning how to deploy applications to Kubernetes of Virtual Machines in cloud, create your own tiny application.

The List Of Web Application Ideas An e-commerce platform where people can buy and sell products online. A platform for booking and managing doctor’s appointments. A social networking site for connecting with friends and family. A task and project management tool for teams and organizations. A recipe and meal planning app for people who want to eat healthy. A travel planning and booking app that helps people plan their trips and find the best deals on flights and accommodations.

Architecture 1: Kubernetes Control Plane Without HA Create three Virtual Machine guests on your laptop or workstation. VM 01 - Kubernetes Control Plane VM 02, VM 03 - Kubernetes Worker nodes Architecture 2: Kubernetes Control Plane With HA Create five Virtual Machine guests on your laptop or workstation. VM 01, VM 02, VM 03 - Kubernetes Control Plane with HA VM 04, VM 05 - Kubernetes Worker nodes Use the Kubeadm tool to create the cluster.

A reference application is a sample application that is used as a guide for developers to learn and implement best practices for software development, testing, deployment, and operations within a specific technology stack or framework. It can serve as a blueprint for building and maintaining similar applications and can be used to demonstrate the use of tools, processes, and techniques for achieving high levels of automation, scalability, and reliability. If you are learning how to deploy applications to Kubernetes of Virtual Machines in cloud, create your own tiny application.

NFS Server To run your own NFS (Network File System) server, you’ll need to first install Linux on your server. I’d go with Debian, Ubuntu or CentOS distributions. Once you’ve done that, you can install the NFS server software, which is typically included with most Linux distributions. After the NFS server software is installed, you’ll need to configure it to specify which directories on the server should be shared with NFS clients, and what type of access they should have.

There are many applications and technologies enabled by VPN. We will focus on one of them in this post: client VPN. Connecting To A Private Network If the server you are trying to access is on a private network, you can use a VPN to connect to the network as if you were physically present on the same network. This can be useful if you need to access resources or devices that are only available on the private network.

syslog Syslog is a standard for logging system events on Unix and Linux systems. It is typically used to collect and store log messages from various applications and system components, such as the kernel, system libraries, and applications. Syslog uses a client-server model, where each client application sends log messages to a central syslog server, which then stores the messages in a log file. The syslog server can also forward the log messages to other syslog servers or send them to a log management system for further analysis.

There are many tools and software programs that can be used for monitoring and performance analysis on Linux systems. Some popular options include: top - This is a command-line utility that shows real-time information about the processes running on a Linux system, such as their CPU and memory usage. htop - This is a more advanced version of top that provides a more user-friendly interface and additional features, such as the ability to sort processes by different metrics and to kill processes.

To run your own email server using Linux and other open source software, you’ll need to first choose a Linux distribution and install it on your server. I’d go with either Ubuntu, Debian or Rocky Linux. Once you’ve done that, you can choose an email server software that is compatible with Linux, such as Postfix or Exim. After installing and configuring the email server software, you’ll need to set up DNS records and configure authentication and encryption to ensure that your email server is secure.

Definition A load balancer is a type of software or hardware that distributes incoming traffic across multiple servers or resources. This allows the load balancer to distribute the workload evenly, improving the performance and availability of the application. The Load Balancer Lab To run your own load balancer using open source software, you will need to: Install and configure the load balancer software on a server. Some popular open source options include HAProxy, Nginx, and Envoy.

Your web applications need a solution to store and retrieve its data. A relational database is often used in web applications. MySQL, MariaDB and PostgreSQL are some popular relational databases. There’s also SQLite. Many applications can use any of these relational databases by the virtue of the database layer abstraction. If you are writing your own web application, pick any one database and install it on your web server. Install The Database Install the package.

Once upon a time, Apache was the de-facto web server solution. Later, Nginx became popular. If you are getting started with DevOps and Linux system administration, I would recommend you to start with Nginx. Start With A Static Website What is a static website? A website made from HTML and CSS. And maybe some JavaScript, images, videos, fonts, etc. The key takeaway is that there is no server side application involved.

As soon as you are ready to deploy services and applications on the Internet, the first thing you need is a registered domain and a DNS server. Often people just use the DNS service provided by the domain registrar or the hosting or cloud provider. Using the managed service is not a requirement. You can host your own DNS server and manage the DNS for your domains. There are many open source software using which you can build your own DNS servers.

A reference application is a sample application that is used as a guide for developers to learn and implement best practices for software development, testing, deployment, and operations within a specific technology stack or framework. It can serve as a blueprint for building and maintaining similar applications and can be used to demonstrate the use of tools, processes, and techniques for achieving high levels of automation, scalability, and reliability. If you are learning how to deploy applications to Kubernetes of Virtual Machines in cloud, create your own tiny application.

The List Of Web Application Ideas An e-commerce platform where people can buy and sell products online. A platform for booking and managing doctor’s appointments. A social networking site for connecting with friends and family. A task and project management tool for teams and organizations. A recipe and meal planning app for people who want to eat healthy. A travel planning and booking app that helps people plan their trips and find the best deals on flights and accommodations.

In a previous post, we discussed using age to manage secrets in Git repositories. In this post, let’s improve our secrets management workflow in Git repositories using SOPS. sops is an editor of encrypted files that supports popular configuration formats such as YAML and various encryption techniques such as age. Read the blog post about age to install the package and creating the key file. This time, we will use sops to perform encryption and decryption operations instead of the age command.

When you begin your career in IT, you will be required to learn Git sooner or later. Git is a key technology used in everyday software engineering and DevOps. It has become persuasive and quintessential. There is no need to hard sell Git to anyone at this point. There is a lot to learn about Git. The good news is that you can start with a subset of Git. There is a no need to become a Git master on your day one of software engineering or DevOps engineering.

Are you storing secrets such as database credentials, API keys, etc. unencrypted in Git repositories? Stop. To protect your secrets, do not store them anywhere unencrypted. Especially in Git repositories. Ideally, your organization must have some vault solution where secrets can be stored and securely shared with people on a need-to-know basis. In many small organizations, having such a central secrets management solution is still a luxury. The need to store such secret information in Git repositories is obvious.

Using Git with SSH is a common practice among software developers. The convenience of not having to remember passwords is a huge productivity boost in software development workflows. In a previous blog post, I wrote about managing SSH keys. Having many SSH keys can cause few issues: ssh-agent doesn’t work well with too many keys. Can’t always map SSH keys to servers in SSH client configuration. Both personal and company projects Git can be hosted on the same server or third-party service such as Github.

In a previous post, we discussed using age to manage secrets in Git repositories. In this post, let’s improve our secrets management workflow in Git repositories using SOPS. sops is an editor of encrypted files that supports popular configuration formats such as YAML and various encryption techniques such as age. Read the blog post about age to install the package and creating the key file. This time, we will use sops to perform encryption and decryption operations instead of the age command.

Are you storing secrets such as database credentials, API keys, etc. unencrypted in Git repositories? Stop. To protect your secrets, do not store them anywhere unencrypted. Especially in Git repositories. Ideally, your organization must have some vault solution where secrets can be stored and securely shared with people on a need-to-know basis. In many small organizations, having such a central secrets management solution is still a luxury. The need to store such secret information in Git repositories is obvious.

In a previous post, we discussed using age to manage secrets in Git repositories. In this post, let’s improve our secrets management workflow in Git repositories using SOPS. sops is an editor of encrypted files that supports popular configuration formats such as YAML and various encryption techniques such as age. Read the blog post about age to install the package and creating the key file. This time, we will use sops to perform encryption and decryption operations instead of the age command.

There are many applications and technologies enabled by VPN. We will focus on one of them in this post: client VPN. Connecting To A Private Network If the server you are trying to access is on a private network, you can use a VPN to connect to the network as if you were physically present on the same network. This can be useful if you need to access resources or devices that are only available on the private network.

Are you storing secrets such as database credentials, API keys, etc. unencrypted in Git repositories? Stop. To protect your secrets, do not store them anywhere unencrypted. Especially in Git repositories. Ideally, your organization must have some vault solution where secrets can be stored and securely shared with people on a need-to-know basis. In many small organizations, having such a central secrets management solution is still a luxury. The need to store such secret information in Git repositories is obvious.

Introduction The article explains how to run your own OpenVPN server. We will create a Certificate Authority Server and an OpenVPN server. We will also generate certificates for the clients. We will also learn how to manage revocation of client certificates using the Ansible roles. Use the Ansible roles gavika.openvpn and gavika.easy_rsa to install and configure your OpenVPN server. You can install the OpenVPN server on any public cloud or hosting provider or on-premise servers.

Ansible comes with a vault feature. It is meant to be used in the context of configuration management. But you can also use it as a standalone simple password vault for your personal or organization’s use. Initial setup of password vault: Create or clone a Git or another SCM repository git init Create the password vault ansible-vault create myvault.secret Type the new master password and confirm, ansible-vault will open your text editor.

In a previous post, we discussed using age to manage secrets in Git repositories. In this post, let’s improve our secrets management workflow in Git repositories using SOPS. sops is an editor of encrypted files that supports popular configuration formats such as YAML and various encryption techniques such as age. Read the blog post about age to install the package and creating the key file. This time, we will use sops to perform encryption and decryption operations instead of the age command.

Are you storing secrets such as database credentials, API keys, etc. unencrypted in Git repositories? Stop. To protect your secrets, do not store them anywhere unencrypted. Especially in Git repositories. Ideally, your organization must have some vault solution where secrets can be stored and securely shared with people on a need-to-know basis. In many small organizations, having such a central secrets management solution is still a luxury. The need to store such secret information in Git repositories is obvious.

When you begin your career in IT, you will be required to learn Git sooner or later. Git is a key technology used in everyday software engineering and DevOps. It has become persuasive and quintessential. There is no need to hard sell Git to anyone at this point. There is a lot to learn about Git. The good news is that you can start with a subset of Git. There is a no need to become a Git master on your day one of software engineering or DevOps engineering.

When you begin your career in IT, you will be required to learn Git sooner or later. Git is a key technology used in everyday software engineering and DevOps. It has become persuasive and quintessential. There is no need to hard sell Git to anyone at this point. There is a lot to learn about Git. The good news is that you can start with a subset of Git. There is a no need to become a Git master on your day one of software engineering or DevOps engineering.

When you begin your career in IT, you will be required to learn Git sooner or later. Git is a key technology used in everyday software engineering and DevOps. It has become persuasive and quintessential. There is no need to hard sell Git to anyone at this point. There is a lot to learn about Git. The good news is that you can start with a subset of Git. There is a no need to become a Git master on your day one of software engineering or DevOps engineering.

NFS Server To run your own NFS (Network File System) server, you’ll need to first install Linux on your server. I’d go with Debian, Ubuntu or CentOS distributions. Once you’ve done that, you can install the NFS server software, which is typically included with most Linux distributions. After the NFS server software is installed, you’ll need to configure it to specify which directories on the server should be shared with NFS clients, and what type of access they should have.

syslog Syslog is a standard for logging system events on Unix and Linux systems. It is typically used to collect and store log messages from various applications and system components, such as the kernel, system libraries, and applications. Syslog uses a client-server model, where each client application sends log messages to a central syslog server, which then stores the messages in a log file. The syslog server can also forward the log messages to other syslog servers or send them to a log management system for further analysis.

There are many applications and technologies enabled by VPN. We will focus on one of them in this post: client VPN. Connecting To A Private Network If the server you are trying to access is on a private network, you can use a VPN to connect to the network as if you were physically present on the same network. This can be useful if you need to access resources or devices that are only available on the private network.

To run your own email server using Linux and other open source software, you’ll need to first choose a Linux distribution and install it on your server. I’d go with either Ubuntu, Debian or Rocky Linux. Once you’ve done that, you can choose an email server software that is compatible with Linux, such as Postfix or Exim. After installing and configuring the email server software, you’ll need to set up DNS records and configure authentication and encryption to ensure that your email server is secure.

Definition A load balancer is a type of software or hardware that distributes incoming traffic across multiple servers or resources. This allows the load balancer to distribute the workload evenly, improving the performance and availability of the application. The Load Balancer Lab To run your own load balancer using open source software, you will need to: Install and configure the load balancer software on a server. Some popular open source options include HAProxy, Nginx, and Envoy.

Once upon a time, Apache was the de-facto web server solution. Later, Nginx became popular. If you are getting started with DevOps and Linux system administration, I would recommend you to start with Nginx. Start With A Static Website What is a static website? A website made from HTML and CSS. And maybe some JavaScript, images, videos, fonts, etc. The key takeaway is that there is no server side application involved.

As soon as you are ready to deploy services and applications on the Internet, the first thing you need is a registered domain and a DNS server. Often people just use the DNS service provided by the domain registrar or the hosting or cloud provider. Using the managed service is not a requirement. You can host your own DNS server and manage the DNS for your domains. There are many open source software using which you can build your own DNS servers.

Introduction The article explains how to run your own OpenVPN server. We will create a Certificate Authority Server and an OpenVPN server. We will also generate certificates for the clients. We will also learn how to manage revocation of client certificates using the Ansible roles. Use the Ansible roles gavika.openvpn and gavika.easy_rsa to install and configure your OpenVPN server. You can install the OpenVPN server on any public cloud or hosting provider or on-premise servers.

Short answer: use ipify ipify provides a simple public address API. Using the tool, you can determine your public IP address programmatically. If you are using the shell: curl 'https://api.ipify.org' Using it in a shell script: my_ip=$(curl 'https://api.ipify.org' -s) echo $my_ip Using the Ansible ipify module: - hosts: localhost vars: tasks: - name: Get my public IP ipify_facts: timeout: 20 delegate_to: localhost register: public_ip - name: output debug: msg="{{ ipify_public_ip }}" Sample output of Ansible playbook execution:

There are many applications and technologies enabled by VPN. We will focus on one of them in this post: client VPN. Connecting To A Private Network If the server you are trying to access is on a private network, you can use a VPN to connect to the network as if you were physically present on the same network. This can be useful if you need to access resources or devices that are only available on the private network.

Introduction The article explains how to run your own OpenVPN server. We will create a Certificate Authority Server and an OpenVPN server. We will also generate certificates for the clients. We will also learn how to manage revocation of client certificates using the Ansible roles. Use the Ansible roles gavika.openvpn and gavika.easy_rsa to install and configure your OpenVPN server. You can install the OpenVPN server on any public cloud or hosting provider or on-premise servers.

There are many tools and software programs that can be used for monitoring and performance analysis on Linux systems. Some popular options include: top - This is a command-line utility that shows real-time information about the processes running on a Linux system, such as their CPU and memory usage. htop - This is a more advanced version of top that provides a more user-friendly interface and additional features, such as the ability to sort processes by different metrics and to kill processes.

To run your own email server using Linux and other open source software, you’ll need to first choose a Linux distribution and install it on your server. I’d go with either Ubuntu, Debian or Rocky Linux. Once you’ve done that, you can choose an email server software that is compatible with Linux, such as Postfix or Exim. After installing and configuring the email server software, you’ll need to set up DNS records and configure authentication and encryption to ensure that your email server is secure.

Definition A load balancer is a type of software or hardware that distributes incoming traffic across multiple servers or resources. This allows the load balancer to distribute the workload evenly, improving the performance and availability of the application. The Load Balancer Lab To run your own load balancer using open source software, you will need to: Install and configure the load balancer software on a server. Some popular open source options include HAProxy, Nginx, and Envoy.

Your web applications need a solution to store and retrieve its data. A relational database is often used in web applications. MySQL, MariaDB and PostgreSQL are some popular relational databases. There’s also SQLite. Many applications can use any of these relational databases by the virtue of the database layer abstraction. If you are writing your own web application, pick any one database and install it on your web server. Install The Database Install the package.

Install PostgreSQL Server Fedora and CentOS: sudo dnf install postgresql-server Ubuntu 18.04: sudo apt install postgresql New Server Initialization On CentOS 7/Fedora 30: sudo postgresql-setup initdb Upgrading From An Older Version sudo postgresql-setup --upgrade Administering The Database Server Managing The postgresql Daemon Starting PostgreSQL server sudo systemctl start postgresql Checking PostgreSQL Server Status: sudo systemctl status postgresql Enabling PostgreSQL Server Systemd Unit/Enabling PostgreSQL Server On Boot: sudo systemctl enable postgresql Allowing Password Based Login From localhost Edit /var/lib/pgsql/data/pg_hba.

In this tutorial, I will provide step-by-step process to implement MySQL replication. We will create one master and one slave. We will use two CentOS 6 servers - one for master and the other for slave. This following steps have been tested on two virtual machines. Our master server will have IP address 192.168.122.10. Our slave server will have IP address 192.168.122.12. You might want to run SELinux in permissive mode.

Once upon a time, Apache was the de-facto web server solution. Later, Nginx became popular. If you are getting started with DevOps and Linux system administration, I would recommend you to start with Nginx. Start With A Static Website What is a static website? A website made from HTML and CSS. And maybe some JavaScript, images, videos, fonts, etc. The key takeaway is that there is no server side application involved.

Once upon a time, Apache was the de-facto web server solution. Later, Nginx became popular. If you are getting started with DevOps and Linux system administration, I would recommend you to start with Nginx. Start With A Static Website What is a static website? A website made from HTML and CSS. And maybe some JavaScript, images, videos, fonts, etc. The key takeaway is that there is no server side application involved.

Learn Linux. Install Linux on your laptop. Get familiar with Linux commands. Learn virtualization. Unlock the path to learn more Linux. Programming. Acquiring some programming skills using a general purpose programming language like Python goes a long way. Learning some web development is required in most DevOps engineering contexts. Although you don’t have to be an expert in web development, you should have a clear understanding of workloads consisting of web applications and microservices.

The blog post attempts to answer some questions like: How to become a DevOps engineer? How to prepare for a DevOps engineer interview? How to get a DevOps engineer job? In a previous blog post, I wrote about the path an aspiring DevOps engineer could follow. In this blog post, I will lay out a concrete plan using which you can prepare yourself for a DevOps engineer job. If you follow the steps carefully, you will be armed with practical DevOps knowledge, and you will be able to apply for DevOps engineer jobs confidently.

The Tech Chorus blog by Sudheer Satyanarayana started way back in 2008. The blog has used various hosting technologies and software over the years. Initially, the blog site used Drupal content management system. LAMP was a popular technology stack those days. Drupal was one of my favorite CMSes back then. The Drupal site was hosted on a cPanel server. As life progressed, there was not enough time to patch Drupal and its plugins.

Learn Linux. Install Linux on your laptop. Get familiar with Linux commands. Learn virtualization. Unlock the path to learn more Linux. Programming. Acquiring some programming skills using a general purpose programming language like Python goes a long way. Learning some web development is required in most DevOps engineering contexts. Although you don’t have to be an expert in web development, you should have a clear understanding of workloads consisting of web applications and microservices.

The blog post attempts to answer some questions like: How to become a DevOps engineer? How to prepare for a DevOps engineer interview? How to get a DevOps engineer job? In a previous blog post, I wrote about the path an aspiring DevOps engineer could follow. In this blog post, I will lay out a concrete plan using which you can prepare yourself for a DevOps engineer job. If you follow the steps carefully, you will be armed with practical DevOps knowledge, and you will be able to apply for DevOps engineer jobs confidently.

The Tech Chorus blog by Sudheer Satyanarayana started way back in 2008. The blog has used various hosting technologies and software over the years. Initially, the blog site used Drupal content management system. LAMP was a popular technology stack those days. Drupal was one of my favorite CMSes back then. The Drupal site was hosted on a cPanel server. As life progressed, there was not enough time to patch Drupal and its plugins.

Learn Linux. Install Linux on your laptop. Get familiar with Linux commands. Learn virtualization. Unlock the path to learn more Linux. Programming. Acquiring some programming skills using a general purpose programming language like Python goes a long way. Learning some web development is required in most DevOps engineering contexts. Although you don’t have to be an expert in web development, you should have a clear understanding of workloads consisting of web applications and microservices.

The blog post attempts to answer some questions like: How to become a DevOps engineer? How to prepare for a DevOps engineer interview? How to get a DevOps engineer job? In a previous blog post, I wrote about the path an aspiring DevOps engineer could follow. In this blog post, I will lay out a concrete plan using which you can prepare yourself for a DevOps engineer job. If you follow the steps carefully, you will be armed with practical DevOps knowledge, and you will be able to apply for DevOps engineer jobs confidently.

As soon as you are ready to deploy services and applications on the Internet, the first thing you need is a registered domain and a DNS server. Often people just use the DNS service provided by the domain registrar or the hosting or cloud provider. Using the managed service is not a requirement. You can host your own DNS server and manage the DNS for your domains. There are many open source software using which you can build your own DNS servers.

The List Of Web Application Ideas An e-commerce platform where people can buy and sell products online. A platform for booking and managing doctor’s appointments. A social networking site for connecting with friends and family. A task and project management tool for teams and organizations. A recipe and meal planning app for people who want to eat healthy. A travel planning and booking app that helps people plan their trips and find the best deals on flights and accommodations.

The List Of Web Application Ideas An e-commerce platform where people can buy and sell products online. A platform for booking and managing doctor’s appointments. A social networking site for connecting with friends and family. A task and project management tool for teams and organizations. A recipe and meal planning app for people who want to eat healthy. A travel planning and booking app that helps people plan their trips and find the best deals on flights and accommodations.

The List Of Web Application Ideas An e-commerce platform where people can buy and sell products online. A platform for booking and managing doctor’s appointments. A social networking site for connecting with friends and family. A task and project management tool for teams and organizations. A recipe and meal planning app for people who want to eat healthy. A travel planning and booking app that helps people plan their trips and find the best deals on flights and accommodations.

If you are wondering how to automate the installation and configuration of Jenkins using code, this post is for you. Jenkins is a popular open source tool to build CI/CD pipelines. Ansible is a popular open source tool to automate a lot of things in IT, including CI/CD and infrastructure orchestration. Ansible can be used to deploy applications in the cloud. Ansible is a nice tool to execute steps such as:

If you are wondering how to automate the installation and configuration of Jenkins using code, this post is for you. Jenkins is a popular open source tool to build CI/CD pipelines. Ansible is a popular open source tool to automate a lot of things in IT, including CI/CD and infrastructure orchestration. Ansible can be used to deploy applications in the cloud. Ansible is a nice tool to execute steps such as:

If you are wondering how to automate the installation and configuration of Jenkins using code, this post is for you. Jenkins is a popular open source tool to build CI/CD pipelines. Ansible is a popular open source tool to automate a lot of things in IT, including CI/CD and infrastructure orchestration. Ansible can be used to deploy applications in the cloud. Ansible is a nice tool to execute steps such as:

This is a blog post in IAC with Terraform series. IAC stands for Infrastructure As Code. Modern IT infrastructure can be orchestrated using programmatic methods. Terraform is(was?) a popular open source software used to orchestrate infrastructure in the cloud and elsewhere too. Terraform has the concept of modules. With modules, you can code abstract infrastructure. For example, if you are creating a pattern of infrastructure over and over again, you could abstract the pattern into a Terraform module.

This is a blog post in IAC with Terraform series. IAC stands for Infrastructure As Code. Modern IT infrastructure can be orchestrated using programmatic methods. Terraform is(was?) a popular open source software used to orchestrate infrastructure in the cloud and elsewhere too. Terraform has the concept of modules. With modules, you can code abstract infrastructure. For example, if you are creating a pattern of infrastructure over and over again, you could abstract the pattern into a Terraform module.

We are pleased to announce gavika.administrators. The Ansible role provides a declarative method to create Linux user accounts with administrative privileges. In other words, these users have sudo access without password and are empowered to run all commands on the system. You might be wondering why you would need a role when you can write a couple tasks yourselves in an Ansible playbook. The reason is, Do Not Repeat Yourself(DRY). Instead of writing such tasks over and over, use the abstraction provided by the role.

Yesterday, we announced the launch of Ansible role to install and configure AWS CloudWatch Agent. You might have seen my other open source Ansible roles on Ansible Galaxy and Github. In the same spirit, the company, Gavika Information Technologies Pvt. Ltd. Bangalore, has started publishing open source projects on Github. Ansible role to install and configure AWS CloudWatch Agent is the first project. Expect more projects in the future. These are some guidelines for the Ansible role projects that Gavika follows:

Last Saturday, the Bangalore PHP User Group conducted a meeting. The venue was same as the last time, Microsoft office, Bangalore! The topic of the meeting was Framework Shootout. The frameworks represented were: Zend Framework CakePHP Symfony WordPress I was glad to get an opportunity to represent the Zend Framework. The slides I presented with Ganesh H S can be downloaded or viewed online at SlideShare. I liked all the presentations.

Today, the Bangalore PHP User Group had a meeting. The meetup.com site reports that sixty eight people attended the meeting. The venue was at Microsoft. The increasing participation of Microsoft in PHP conferences and meetings have taken many by surprise. Microsoft were kind enough to offer free Pizza for all the attendees. They have given me a copy of Windows 7 Release Candidate which expires on June 1, 2010. If time permits, I will sure try to install it as a virtual guest.

This is a blog post in IAC with Terraform series. IAC stands for Infrastructure As Code. Modern IT infrastructure can be orchestrated using programmatic methods. Terraform is(was?) a popular open source software used to orchestrate infrastructure in the cloud and elsewhere too. Terraform has the concept of modules. With modules, you can code abstract infrastructure. For example, if you are creating a pattern of infrastructure over and over again, you could abstract the pattern into a Terraform module.

This is a blog post in IAC with Terraform series. IAC stands for Infrastructure As Code. Modern IT infrastructure can be orchestrated using programmatic methods. Terraform is(was?) a popular open source software used to orchestrate infrastructure in the cloud and elsewhere too. Terraform has the concept of modules. With modules, you can code abstract infrastructure. For example, if you are creating a pattern of infrastructure over and over again, you could abstract the pattern into a Terraform module.

The Tech Chorus blog by Sudheer Satyanarayana started way back in 2008. The blog has used various hosting technologies and software over the years. Initially, the blog site used Drupal content management system. LAMP was a popular technology stack those days. Drupal was one of my favorite CMSes back then. The Drupal site was hosted on a cPanel server. As life progressed, there was not enough time to patch Drupal and its plugins.

In this blog post, I will explain how I implemented a graph algorithm to solve the database migration problem in an application pluggable module system. Prerequisites: Working knowledge of Python Working knowledge of Graph Theory. Familiar with the terms: Edge, vertex, path, sink, source, digraph, path graph, etc. Gavika Web Framework has a pluggable module system. The modules can be developed independently. They can be installed, upgraded and removed from the main application.

In this blog post, I will explain how I implemented a graph algorithm to solve the database migration problem in an application pluggable module system. Prerequisites: Working knowledge of Python Working knowledge of Graph Theory. Familiar with the terms: Edge, vertex, path, sink, source, digraph, path graph, etc. Gavika Web Framework has a pluggable module system. The modules can be developed independently. They can be installed, upgraded and removed from the main application.

AWS Certified Solutions Architect - Associate is one of the most sought-after certifications in the IT industry. Here’s a few tips for those seeking this certification. Background Knowledge And Experience AWS recommends “at least one year of hands-on experience designing available, cost-efficient, fault-tolerant, and scalable and distributed systems on AWS.” In other words, if you recently started your career in IT, there are a few things you have to do before you start preparing for this certification.

Install the Ansible role gavika.aws_cloudwatchagent via Galaxy ansible-galaxy install gavika.aws_cloudwatchagent Create The Playbook File - cw-play.yml : --- - hosts: all become: true vars: roles: - role: gavika.aws_cloudwatchagent Prepare the AWS CloudWatch Agent configuration In your variables file, use aws_cloudwatch_agent_config agent: metrics_collection_interval: 60 run_as_user: "cwagent" metrics: namespace: "Gavika" append_dimensions: InstanceId: "${aws:InstanceId}" metrics_collected: disk: measurement: - used_percent metrics_collection_interval: 60 resources: - "*" mem: measurement: - mem_used_percent metrics_collection_interval: 60 In this example, I am using the namespace, Gavika.

AWS Certified Solutions Architect - Associate is one of the most sought-after certifications in the IT industry. Here’s a few tips for those seeking this certification. Background Knowledge And Experience AWS recommends “at least one year of hands-on experience designing available, cost-efficient, fault-tolerant, and scalable and distributed systems on AWS.” In other words, if you recently started your career in IT, there are a few things you have to do before you start preparing for this certification.

Introduction The article explains how to run your own OpenVPN server. We will create a Certificate Authority Server and an OpenVPN server. We will also generate certificates for the clients. We will also learn how to manage revocation of client certificates using the Ansible roles. Use the Ansible roles gavika.openvpn and gavika.easy_rsa to install and configure your OpenVPN server. You can install the OpenVPN server on any public cloud or hosting provider or on-premise servers.

We are pleased to announce gavika.administrators. The Ansible role provides a declarative method to create Linux user accounts with administrative privileges. In other words, these users have sudo access without password and are empowered to run all commands on the system. You might be wondering why you would need a role when you can write a couple tasks yourselves in an Ansible playbook. The reason is, Do Not Repeat Yourself(DRY). Instead of writing such tasks over and over, use the abstraction provided by the role.

Yesterday, we announced the launch of Ansible role to install and configure AWS CloudWatch Agent. You might have seen my other open source Ansible roles on Ansible Galaxy and Github. In the same spirit, the company, Gavika Information Technologies Pvt. Ltd. Bangalore, has started publishing open source projects on Github. Ansible role to install and configure AWS CloudWatch Agent is the first project. Expect more projects in the future. These are some guidelines for the Ansible role projects that Gavika follows:

We are pleased to announce gavika.administrators. The Ansible role provides a declarative method to create Linux user accounts with administrative privileges. In other words, these users have sudo access without password and are empowered to run all commands on the system. You might be wondering why you would need a role when you can write a couple tasks yourselves in an Ansible playbook. The reason is, Do Not Repeat Yourself(DRY). Instead of writing such tasks over and over, use the abstraction provided by the role.

Yesterday, we announced the launch of Ansible role to install and configure AWS CloudWatch Agent. You might have seen my other open source Ansible roles on Ansible Galaxy and Github. In the same spirit, the company, Gavika Information Technologies Pvt. Ltd. Bangalore, has started publishing open source projects on Github. Ansible role to install and configure AWS CloudWatch Agent is the first project. Expect more projects in the future. These are some guidelines for the Ansible role projects that Gavika follows:

Last Saturday, the Bangalore PHP User Group conducted a meeting. The venue was same as the last time, Microsoft office, Bangalore! The topic of the meeting was Framework Shootout. The frameworks represented were: Zend Framework CakePHP Symfony WordPress I was glad to get an opportunity to represent the Zend Framework. The slides I presented with Ganesh H S can be downloaded or viewed online at SlideShare. I liked all the presentations.

Today, the Bangalore PHP User Group had a meeting. The meetup.com site reports that sixty eight people attended the meeting. The venue was at Microsoft. The increasing participation of Microsoft in PHP conferences and meetings have taken many by surprise. Microsoft were kind enough to offer free Pizza for all the attendees. They have given me a copy of Windows 7 Release Candidate which expires on June 1, 2010. If time permits, I will sure try to install it as a virtual guest.

Short answer: use ipify ipify provides a simple public address API. Using the tool, you can determine your public IP address programmatically. If you are using the shell: curl 'https://api.ipify.org' Using it in a shell script: my_ip=$(curl 'https://api.ipify.org' -s) echo $my_ip Using the Ansible ipify module: - hosts: localhost vars: tasks: - name: Get my public IP ipify_facts: timeout: 20 delegate_to: localhost register: public_ip - name: output debug: msg="{{ ipify_public_ip }}" Sample output of Ansible playbook execution:

Moving around You can use the arrow keys on keyboard to move around in the command line. Bash also provides convenient keyboard shortcuts to navigate effectively. Try them out and see for yourself. To become a Bash pro user you have to get yourself familiar with the keyboard shortcuts. Once you do, you’ll find yourself productive. Shortcut Description CTRL+b move backward one character CTRL+f move forward one character ESC+b move one word backward ESC+f move one word forward CTRL+a move to beginning of line CTRL+e move to end of line CTRL+p move to previous line CTRL+n move to next line ESC+< move to first line of history list ESC+> move to last line of history list Moving around words using ESC+f and ESC+b are my favourites in this list.

Install the Ansible role gavika.aws_cloudwatchagent via Galaxy ansible-galaxy install gavika.aws_cloudwatchagent Create The Playbook File - cw-play.yml : --- - hosts: all become: true vars: roles: - role: gavika.aws_cloudwatchagent Prepare the AWS CloudWatch Agent configuration In your variables file, use aws_cloudwatch_agent_config agent: metrics_collection_interval: 60 run_as_user: "cwagent" metrics: namespace: "Gavika" append_dimensions: InstanceId: "${aws:InstanceId}" metrics_collected: disk: measurement: - used_percent metrics_collection_interval: 60 resources: - "*" mem: measurement: - mem_used_percent metrics_collection_interval: 60 In this example, I am using the namespace, Gavika.

Ansible comes with a vault feature. It is meant to be used in the context of configuration management. But you can also use it as a standalone simple password vault for your personal or organization’s use. Initial setup of password vault: Create or clone a Git or another SCM repository git init Create the password vault ansible-vault create myvault.secret Type the new master password and confirm, ansible-vault will open your text editor.

Install PostgreSQL Server Fedora and CentOS: sudo dnf install postgresql-server Ubuntu 18.04: sudo apt install postgresql New Server Initialization On CentOS 7/Fedora 30: sudo postgresql-setup initdb Upgrading From An Older Version sudo postgresql-setup --upgrade Administering The Database Server Managing The postgresql Daemon Starting PostgreSQL server sudo systemctl start postgresql Checking PostgreSQL Server Status: sudo systemctl status postgresql Enabling PostgreSQL Server Systemd Unit/Enabling PostgreSQL Server On Boot: sudo systemctl enable postgresql Allowing Password Based Login From localhost Edit /var/lib/pgsql/data/pg_hba.

Install PostgreSQL Server Fedora and CentOS: sudo dnf install postgresql-server Ubuntu 18.04: sudo apt install postgresql New Server Initialization On CentOS 7/Fedora 30: sudo postgresql-setup initdb Upgrading From An Older Version sudo postgresql-setup --upgrade Administering The Database Server Managing The postgresql Daemon Starting PostgreSQL server sudo systemctl start postgresql Checking PostgreSQL Server Status: sudo systemctl status postgresql Enabling PostgreSQL Server Systemd Unit/Enabling PostgreSQL Server On Boot: sudo systemctl enable postgresql Allowing Password Based Login From localhost Edit /var/lib/pgsql/data/pg_hba.

You access Python dictionary keys using the syntax: my_dicy[my_key] For example: >>> my_dict = {'food': 'idly'} >>> my_dict['food'] 'idly' Sometimes, you might want to access the dictionary keys using: my_dict.my_key syntax. If you do this is what happens: >>> my_dict.food Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'dict' object has no attribute 'food' How can you solve this? Easy. pip install attrdict How do you use the newly installed package?

In this tutorial, I will provide step-by-step process to implement MySQL replication. We will create one master and one slave. We will use two CentOS 6 servers - one for master and the other for slave. This following steps have been tested on two virtual machines. Our master server will have IP address 192.168.122.10. Our slave server will have IP address 192.168.122.12. You might want to run SELinux in permissive mode.

In this tutorial, I will provide step-by-step process to implement MySQL replication. We will create one master and one slave. We will use two CentOS 6 servers - one for master and the other for slave. This following steps have been tested on two virtual machines. Our master server will have IP address 192.168.122.10. Our slave server will have IP address 192.168.122.12. You might want to run SELinux in permissive mode.

In this tutorial, I will provide step-by-step process to implement MySQL replication. We will create one master and one slave. We will use two CentOS 6 servers - one for master and the other for slave. This following steps have been tested on two virtual machines. Our master server will have IP address 192.168.122.10. Our slave server will have IP address 192.168.122.12. You might want to run SELinux in permissive mode.

If you have to insert a comment on several lines do you do manually insert the comment character in every line? Stop. Vim is a good editor and has a nice feature to accomplish this quickly. Here are the steps: Enter visual blocking mode by pressing CTRL V (CTRL key and the lowercase v). Make your selection using motion keys(jklm, etc.). Press I(uppercase I) to enter block insert mode. Press #, the comment character.

If you have to insert a comment on several lines do you do manually insert the comment character in every line? Stop. Vim is a good editor and has a nice feature to accomplish this quickly. Here are the steps: Enter visual blocking mode by pressing CTRL V (CTRL key and the lowercase v). Make your selection using motion keys(jklm, etc.). Press I(uppercase I) to enter block insert mode. Press #, the comment character.

If you have to insert a comment on several lines do you do manually insert the comment character in every line? Stop. Vim is a good editor and has a nice feature to accomplish this quickly. Here are the steps: Enter visual blocking mode by pressing CTRL V (CTRL key and the lowercase v). Make your selection using motion keys(jklm, etc.). Press I(uppercase I) to enter block insert mode. Press #, the comment character.

Moving around You can use the arrow keys on keyboard to move around in the command line. Bash also provides convenient keyboard shortcuts to navigate effectively. Try them out and see for yourself. To become a Bash pro user you have to get yourself familiar with the keyboard shortcuts. Once you do, you’ll find yourself productive. Shortcut Description CTRL+b move backward one character CTRL+f move forward one character ESC+b move one word backward ESC+f move one word forward CTRL+a move to beginning of line CTRL+e move to end of line CTRL+p move to previous line CTRL+n move to next line ESC+< move to first line of history list ESC+> move to last line of history list Moving around words using ESC+f and ESC+b are my favourites in this list.

Moving around You can use the arrow keys on keyboard to move around in the command line. Bash also provides convenient keyboard shortcuts to navigate effectively. Try them out and see for yourself. To become a Bash pro user you have to get yourself familiar with the keyboard shortcuts. Once you do, you’ll find yourself productive. Shortcut Description CTRL+b move backward one character CTRL+f move forward one character ESC+b move one word backward ESC+f move one word forward CTRL+a move to beginning of line CTRL+e move to end of line CTRL+p move to previous line CTRL+n move to next line ESC+< move to first line of history list ESC+> move to last line of history list Moving around words using ESC+f and ESC+b are my favourites in this list.

Last Saturday, the Bangalore PHP User Group conducted a meeting. The venue was same as the last time, Microsoft office, Bangalore! The topic of the meeting was Framework Shootout. The frameworks represented were: Zend Framework CakePHP Symfony WordPress I was glad to get an opportunity to represent the Zend Framework. The slides I presented with Ganesh H S can be downloaded or viewed online at SlideShare. I liked all the presentations.

Today, the Bangalore PHP User Group had a meeting. The meetup.com site reports that sixty eight people attended the meeting. The venue was at Microsoft. The increasing participation of Microsoft in PHP conferences and meetings have taken many by surprise. Microsoft were kind enough to offer free Pizza for all the attendees. They have given me a copy of Windows 7 Release Candidate which expires on June 1, 2010. If time permits, I will sure try to install it as a virtual guest.

Last Saturday, the Bangalore PHP User Group conducted a meeting. The venue was same as the last time, Microsoft office, Bangalore! The topic of the meeting was Framework Shootout. The frameworks represented were: Zend Framework CakePHP Symfony WordPress I was glad to get an opportunity to represent the Zend Framework. The slides I presented with Ganesh H S can be downloaded or viewed online at SlideShare. I liked all the presentations.

Last Saturday, the Bangalore PHP User Group conducted a meeting. The venue was same as the last time, Microsoft office, Bangalore! The topic of the meeting was Framework Shootout. The frameworks represented were: Zend Framework CakePHP Symfony WordPress I was glad to get an opportunity to represent the Zend Framework. The slides I presented with Ganesh H S can be downloaded or viewed online at SlideShare. I liked all the presentations.

Today, the Bangalore PHP User Group had a meeting. The meetup.com site reports that sixty eight people attended the meeting. The venue was at Microsoft. The increasing participation of Microsoft in PHP conferences and meetings have taken many by surprise. Microsoft were kind enough to offer free Pizza for all the attendees. They have given me a copy of Windows 7 Release Candidate which expires on June 1, 2010. If time permits, I will sure try to install it as a virtual guest.

As per the Wikipedia “alpha compositing is the process of combining an image with a background to create the appearance of partial transparency”. To remove the transparency or the alpha channel: Fire up GIMP Open the image for which the alpha channel has to be removed Click the Image menu on the image window Click Flatten Image from the pull down menu Save In short, remember to flatten the image when you want to remove the alpha channel.

As per the Wikipedia “alpha compositing is the process of combining an image with a background to create the appearance of partial transparency”. To remove the transparency or the alpha channel: Fire up GIMP Open the image for which the alpha channel has to be removed Click the Image menu on the image window Click Flatten Image from the pull down menu Save In short, remember to flatten the image when you want to remove the alpha channel.

If you are wondering how to automate the installation and configuration of Jenkins using code, this post is for you. Jenkins is a popular open source tool to build CI/CD pipelines. Ansible is a popular open source tool to automate a lot of things in IT, including CI/CD and infrastructure orchestration. Ansible can be used to deploy applications in the cloud. Ansible is a nice tool to execute steps such as: