Docker Volumes are a key feature that allow you to persist data generated by and used by Docker containers. Volumes are stored on the host filesystem outside the container's filesystem, so they are not deleted when the container is removed, making them ideal for persisting data like database files, logs, and configuration files. Example: Using Docker Volumes 1. Creating a Simple Container with a Volume Let's create a simple Docker container using the official nginx image and attach a volume to persist data. docker run -d --name my-nginx -v /mydata:/usr/share/nginx/html:ro -p 8080:80 nginx Explanation: -d : Runs the container in detached mode (in the background). --name my-nginx : Names the container my-nginx . -v /mydata:/usr/share/nginx/html:ro : Creates a volume that maps the host directory /mydata to the container directory /usr/share/nginx/html . The :ro option makes this volume read-only inside the container. -p 8080:80 : Maps port 8080 on the host to port 80 in the con
Why DevOps: Addressing Shortfalls of Previous Methodologies DevOps emerged as a response to the limitations of previous software development methodologies, aiming to improve collaboration, automate processes, and accelerate delivery. Here's an exploration of why DevOps became necessary, with explanations of the shortcomings of earlier methodologies using examples and analogies. Traditional Methodologies and Their Shortfalls Waterfall Model Description : A linear and sequential approach where each phase (Requirements, Design, Implementation, Verification, Maintenance) must be completed before the next one begins. Shortfalls : Rigidity : Changes are difficult and costly once a phase is completed. Late Testing : Testing only occurs after the implementation phase, leading to the discovery of major issues late in the process. Customer Feedback : Limited to the beginning (requirements) and end (deployment) phases, risking the final product not meeting user needs. Analogy : Building a h