◐/

BROWSE108 notes

Filter notes/

Enter opens the top match. Use /regex/i for patterns.

▸Software Enginner1

▾Images & Registry5

docker images & rmi

▸Networking & Storage2

▸Troubleshooting7

▸Kubernetes16

▸GitHub Actions15

Fix bugs or Add features docker system prune curl API testing: repeat 100×, load & timing Install .deb files & alternative install methods (Ubuntu)

⌂Home ◐Search◎Graph

Docker/Images & Registry/docker tag

CommandUpdated 3 weeks ago

docker tag

Gives an existing image an additional name — most often to point it at a registry before pushing.

#docker #images #registry

Command

Tag for a registry

SHELL

1docker tag <image>:<tag> <registry>/<image>:<tag>

2

3# e.g.

4docker tag myapp:latest ghcr.io/myorg/myapp:v1.2.0

How tags work

A tag is just a pointer to an image ID. Tagging copies nothing and uses no disk: docker images shows several names with the same IMAGE ID.

Syntax: docker tag <source>[:tag] [registry/][namespace/]name[:tag]

Tagging strategy

Common patterns

SHELL

1# Semantic version + moving tags

2docker tag myapp:1.4.2 <user>/myapp:1.4.2

3docker tag myapp:1.4.2 <user>/myapp:1.4

4docker tag myapp:1.4.2 <user>/myapp:latest

5

6# Git commit SHA for traceable deploys

7docker tag myapp <user>/myapp:$(git rev-parse --short HEAD)

8

9# Tag at build time instead (multiple -t allowed)

10docker build -t <user>/myapp:1.4.2 -t <user>/myapp:latest .

Gotchas

Moving a tag to a new build leaves the old image dangling (<none>:<none>); clean up with docker image prune
docker rmi <name:tag> removes only that tag while other tags still point to the image
Deploy immutable tags (version or SHA), not latest, so rollbacks are exact

On this page

Command How tags work Tagging strategy Gotchas

Referenced by3

Uploads a tagged image to a registry so it can be pulled elsewhere — the last step before a deploy picks it up.

Builds an image from a Dockerfile — each instruction becomes a cached layer, so unchanged steps stay fast on rebuild.

docker images & rmi

List the images stored locally, see what uses disk, and remove the ones you no longer need.

Leads to

relateddocker build relateddocker push

History

3 weeksEdited "docker tag"