Training-10-2023

What is Docker?
Docker is a platform for developing, shipping, and running applications in containers. Containers are lightweight, standalone, and executable packages that include everything needed to run an application, including the code, runtime, system tools, libraries, and settings. Docker uses containerization technology to create and manage these containers.
Pros of using Docker:
1. Isolation: Docker containers encapsulate applications and their dependencies, ensuring that they run consistently across different environments, from development to production. This eliminates the "it works on my machine" problem.
2. Portability: Containers can run on any system that supports Docker, making it easy to move applications between different environments and cloud providers.
3. Resource Efficiency: Docker containers share the host OS kernel, reducing overhead and allowing for the efficient use of system resources.
4. Scalability: Docker makes it easy to scale applications horizontally by spinning up multiple instances of containers to handle increased workloads.
5. Version Control: You can version control your Docker images, making it easier to track changes and roll back to previous versions if needed.
6. Microservices: Docker is often used in microservices architectures, where applications are broken down into smaller, independently deployable services.
7. Ecosystem: Docker has a vast ecosystem of tools and services, making it easier to integrate with other DevOps and cloud technologies.
Cons of using Docker:
1. Learning Curve: Docker has a learning curve, especially for those new to containerization concepts.
2. Resource Overhead: While Docker containers are more resource-efficient than traditional virtual machines, they still have some overhead due to the containerization layer.
3. Security: Docker security requires careful configuration to ensure containers are properly isolated and that sensitive data is protected.
4. Orchestration Complexity: Managing a large number of containers in a production environment can be complex, often requiring container orchestration tools like Kubernetes.
What is docker-compose?
Docker Compose is a tool used to define and run multi-container setups for Docker applications. With Compose, you employ a YAML file to configure services for your application. Subsequently, you utilize commands to create and run containers based on those configurations.
Common docker/docker-compose commands
1. docker –version
2. docker search,docker pull
3. docker images,docker run
4. docker ps
5. docker stop
6. docker start
7. docker rm
8. docker exec