Same repository, tag and image ID - but different digests


#1

Can somebody help me understand what’s going on here?

❯ docker image ls --digests node
REPOSITORY          TAG                 DIGEST                                                                    IMAGE ID            CREATED             SIZE
node                8.11.1-alpine       sha256:1b1928c9eea9e6cd5ff6155a2adda33a022a08911a1418f5ebe8ff992abd2a69   e707e7ad7186        40 hours ago        68.1MB
node                8.11.1-alpine       sha256:7daef4e511bcd3655c18cb58bfc382a4391b04c7881c4debc17a5882908917e4   e707e7ad7186        40 hours ago        68.1MB

I thought that digests uniquely identify an image, so they should be different. I thought maybe one replaced the other, but this output shows them as both 40 hours ago.


#2

#3

@meruguchandra that’s different; similar to git, you can tag an image under multiple names, so the same sha can be used for multiple images.

@rarkins I suspect this is a presentation issue, but we’d need more information: can you open an issue in https://github.com/moby/moby/issues, and:

  • provide the requested information (docker version, docker info)
  • provide docker image inspect output for both the 1b1928c9eea9e6cd5ff6155a2adda33a022a08911a1418f5ebe8ff992abd2a69 and 7daef4e511bcd3655c18cb58bfc382a4391b04c7881c4debc17a5882908917e4 image?