Docker
From DWIKI
Links
Docs
- Docker-compose
- https://www.digitalocean.com/community/tutorials/how-to-install-and-use-docker-on-centos-7
- Removing images, containers and volumes
- Docker for beginners
- Docker networking
- Docker pruning
HOWTO
List running containers
docker ps
List containers
docker ps -a
Show disk usage
docker system df
outputs:
TYPE TOTAL ACTIVE SIZE RECLAIMABLE Images 27 10 11.35GB 5.72GB (50%) Containers 12 12 123.6MB 0B (0%) Local Volumes 0 0 0B 0B Build Cache 0 0 0B 0B
RECLAIMABLE
Is what you get back when running
docker prune a
List images
docker images
Export image
docker save <image name> > imagename.tar
Get shell in running container
To get image name
docker ps
then
docker exec -it <image-id> bash
Network
docker network ls docker network inspect
image has dependent child images
docker inspect --format='Template:.Id Template:.Parent' $(docker images --filter since=<image_id> -q)
Dangling images
list dangling images
docker images -f dangling=true
Remove dangling image
docker rmi image-id
Remove all dangling images
docker rmi $(docker images -f dangling=true -q)
image is being used by stopped container xyz
docker rm xyz
and try again
Backups
FAQ
Error messages
The container name "/mycontainer" is already in use by container
It already exists, so use
docker start
instead of
docker run
docker.service: Start request repeated too quickly
Try
dockerd --debug
dial unix /var/run/docker.sock: connect: permission denied
You're not in group docker
Compose
unknown shorthand flag: 'd' in -d
docker-compose is probably a script/wrapper. Install the
docker: 'compose' is not a docker command.
Check https://docs.docker.com/engine/install/debian/
unknown flag: --detach
apt install docker-compose-v2
image is being used by stopped container
use the force
