#devops

Articles tagged with #devops

Ansible Playbooks Explained: From First YAML File to Managing Real Servers
If you have already run a few Ansible ad hoc commands and seen how they work, you already understand the core idea: one command, many servers. But ad hoc commands only take you so far. When you need to install software, start services, create users, copy files, and print confirmation messages, all in one automated run across multiple servers, that is when you move to playbooks. Playbooks are where Ansible truly earns its place in a DevOps workflow. Everything you do in Ansible at scale, you do through playbooks.
Jun 19, 202613 min read1
Docker Compose in Action: Multi-Container Apps, Nginx Load Balancing & Docker Hub
We built four containerized microservices for an bank application in the last post. Internet banking, mobile banking, insurance, and loans, each running in its own container, each exposed on a separate port. The setup worked. But the process of building and running each container individually by hand was repetitive, error-prone, and simply not practical at scale. This post introduces Docker Compose, and by the end, you will understand not just how to use it, but why it exists, what its real limitations are, how to combine it with Nginx to build a working high availability architecture, and how to push your images to Docker Hub so they are available beyond your local machine. There is also a hands-on project included here that builds a Flask-based Python application behind an Nginx load balancer, which you are expected to complete as a practical exercise.
Jun 16, 202617 min read1
From Monolith to Microservices: Building Multi-Container Apps with Docker
Before we get into Docker Compose, we need to set the stage with a real-world problem. Because Docker Compose does not make sense in isolation. It makes sense once you have felt the pain of managing multiple containers by hand. So let us start with an example that most of us interact with every day. A bank. Specifically, we are going to use Bank as our reference architecture for this entire session, and honestly, for the rest of this series all the way through Kubernetes. Pay attention to this example because it is not just a throwaway analogy. We are going to build on it, extend it, and carry it forward. Every concept we introduce from here will connect back to it.
Jun 15, 202610 min read1
Understanding Dockerfiles: From Basics to Real-World Deployment
If you have been working with Docker for even a short time, you have probably heard this phrase thrown around: "just write a Dockerfile." But what does that actually mean, and how does it work under the hood? In this article, we are going to walk through Dockerfiles the same way a classroom session would. We will start from the very basics, build up through each component one at a time, and finish with a real-world deployment where you host an actual web application and a Tomcat server running Jenkins inside Docker containers. Before this, you may have created Docker images by spinning up a container, manually installing things inside it, and then running docker commit to snapshot that container into an image. That works, but it is not the right approach in practice. It is manual, error-prone, and not repeatable. The correct and professional way to create images is through a Dockerfile.
Jun 14, 202618 min read9
Docker Container Lifecycle: Every Command You Need to Know
If you are learning Docker seriously, there is one thing you need to accept early. Knowing what a container is means very little if you do not know how to manage one. Starting, stopping, pausing, logging in, copying files, checking memory usage, saving images, and cleaning up - all of this is what makes the difference between someone who has heard of Docker and someone who can actually work with it. This article walks through everything a working Docker environment demands. We are going through the full container lifecycle with real commands, real explanations, and the kind of detail that actually stays with you. By the end, you will have a solid reference for your daily work and your interviews.
Jun 14, 202615 min read3
What Is Jenkins and Why Every DevOps Engineer Needs to Understand CI/CD Pipelines
If you have been wondering what Jenkins actually does, or why DevOps engineers keep talking about CI/CD pipelines, this post is going to clear all of that up. We are going to start from the very beginning and build a solid mental model before touching a single command.
Jun 9, 20267 min read

#devops - Sai Praneeth's Blogs