Docker is a platform for developing, shipping, and running applications using container technology. It allows developers to package applications and their dependencies into lightweight, portable containers that can run on any machine with Docker installed. Docker enables efficient and consistent deployment of applications across different environments, making it an essential tool for modern software development and deployment.
docker pull: Pulls a Docker image from a registry (like Docker Hub).docker run: Runs a container from a Docker image.docker ps: Lists all running containers.docker build: Builds a Docker image from a Dockerfile.docker stop: Stops a running container.docker rm: Removes a stopped container.docker rmi: Removes a Docker image.docker logs: Fetches the logs of a container.docker exec: Runs a command in a running container.Example of a simple Dockerfile for a Node.js application:
# Use an official Node.js runtime as a parent image
FROM node:14
# Set the working directory in the container
WORKDIR /usr/src/app
# Copy the package.json and package-lock.json files
COPY package*.json ./
# Install dependencies
RUN npm install
# Copy the rest of the application code
COPY . .
# Expose the application port
EXPOSE 8080
# Define the command to run the application
CMD ["node", "app.js"]
Docker is a powerful tool that can greatly simplify the deployment and management of applications. By understanding the basics and utilizing the resources available, Linux server administrators can effectively leverage Docker to improve their workflows and system reliability.