Docker

Question 1

Components of docker

Answer 1

1. Dockerfile
2. Docker image
3. Docker container

Question 2

Why is containerisation used

Answer 2

If a container can run one a machine, it can run on another machine. Don’t have to use a VM for every app

Question 3

Downsides of containerisation

Answer 3

1. To run the containers, need to have docker installed
2. Images and containers can take up space. Images and containers get lost and can result in illegal stuff if not monitored

Question 4

Docker networking steps

Answer 4

1. external client calls docker host ip with port number
2. Docker engine maps the request with the port mapping to the internal IP of the docker container with the port number according to port mapping
   5001: 5000 -> external call 5001, it maps to 5000 of an internal app

Question 5

How does a container interact outside

Answer 5

calling host.docker.internal (ie localhost of the docker host)