无需拉取镜像，如何远程为Docker镜像打标签并推送？

Do you need to pull the image before tagging it? #

Short answer: No—if the image already exists locally.

The docker tag command only works with images stored on your local Docker daemon. Here's the breakdown:

• If image:1 is already on your machine, you can run docker tag image:1 image:2 directly without pulling first. A tag is just a lightweight alias pointing to the same underlying image ID—no new data is copied.
• If image:1 isn't present locally, running docker tag will throw an error like Error response from daemon: No such image: image:1—in that case, you do need to pull it first to get it onto your system.

Can you simplify the workflow for tagging and pushing? #

Absolutely! You can cut out the redundant pull step entirely when the image is already local. The minimal seamless workflow looks like this:

1. Tag the local image (skip pull if it's already stored locally):

   docker tag image:1 image:2
   

2. Push the new tag to your repository:

   docker push image:2
   

If the image isn't local, you can't tag a remote image directly (Docker requires the image to exist locally to create an alias). But you can chain the commands to streamline the full pull-tag-push process:

docker pull image:1 && docker tag image:1 image:2 && docker push image:2

This way, if the pull succeeds, the tag and push run automatically. If the pull fails (e.g., wrong image name), the rest of the commands won't execute.

A quick note: When you push image:2, Docker will recognize it shares the same image ID as image:1, so it won't upload duplicate layers to the registry. This makes the push fast even for large images!

内容的提问来源于stack exchange，提问作者Ramboo19