Docker

WIP

PC vs VM vs Containers

VM you split up resources and is quite heavy Containers shares the resources but has environments set up

Docker

Uses an image to create a container

• An image can be made up of a few programs. Lets say your application needs python, mySQL. That image will contain those.

docker [OPTIONS] command
docker help
docker run -d -p 80:80 docker/getting-started:latest
docker ps - shows what dockers are running
docker stop CONTAINER_ID
docker kill CONTAINER_ID
docker images
docker exec CONTAINER_ID ls
	list dirs in that container

docker run -d -e NODE_ENV=development -e url=http://localhost:3001 -p 3001:2368 -v ghost-vol:/var/lib/ghost/content ghost

docker rm CONTAINER_ID
docker volume rm VOLUME_NAME

Need to stop then remove container before you're allowed to remove volume.

Isolating container via offline mode

Example: if you want students to run code on machines. Auditing a malware in a container. Running sussy program that you dont want access to network.

Load balancing

We don't want server(s) to get overwealmed. So we have something to balance the load. So we split traffic to different servers. Many different ways.

• Round Robin is one of them. Client 1 -> Server 1. Client 2 -> Server 2. Client 3 -> Server 3. Client 4 -> Server 1.

docker run -p 8001:80 -v $PWD/index1.html:/usr/share/caddy/index.html caddy

CI/CD pipeline

Code -> Commit -> Push -> Pull Request -> Merged -> builds -> Image built -> Pushed to DockerHub -> K8s docker pull -> restart containers

The 2nd and 3rd pieces should be automated. To help deploy the latest software. All backend work.