docker-learning

1. What is docker?

Dcocker is open-source centralized platform designed to create, deploy and run applications.

2. Why do we need docker?

• Compatability/dependacies
• Long set up time
• Different dev/test/prod enviornment

3. Why do we prefer docker over virtulization?

   1. Problems with virtulization:

      • Wastage of resourses.
      • Limitation on sharing resources.
      • Each V.M have their own OS which makes them heavy and therefore it utilizes more space.

   2. Problems solved by using docker:

      • Docker produces containers.
      • container has all dependencies which is required to run the app and if it doesn't have any it will take from docker hub.
      • Container does not have their own OS and hence they are light weight.
      • They will use resourses from host OS only when they are running.

   3. Containers vs Virtual machine:

   

   4. Docker basic commands:

      1. Run: Start a container

         eg: docker run <image name>

      2. ps: List containers

         • List running containers:
           eg: docker ps
         • List all containers:
           eg: docker ps -a

      3. Stop: stop a container:

         eg: docker stop <container name/id>

      4. rm: remove a container:

         eg: docker rm <container name/id>

      5. images: List images:

         eg: docker images

      6. rmi: remove images:

         eg: docker rmi <image name>

      7. pull: download and image:

         eg: docker pull <image name>

      8. exec: execute a commnad on running container:

         eg: docker exec <container name> <command>

      9. inspect: to know more info about container:

         eg: docker inspect <container name>

      10. logs: to see the logs of container:

          eg: docker logs <conatiner name>