Prune old docker images - any howto?

AI-generated summary

The discussion revolves around pruning old Docker images. nordize has multiple images from upgrading Discourse via Docker and wants to know how to keep only the necessary ones. They’re unsure about the different image names (local_discourse/app, discourse/base, discourse/discourse) and would like a general “housekeeping” guide to keep only the last 3 images.

In response, pfaffman suggests running ./launcher cleanup to achieve this goal.

I’ve had Discourse installed for a while via docker and performed many upgrades in the last few years. Now I ended up with quite a few docker images:

# docker images
REPOSITORY                      TAG                 IMAGE ID            CREATED             SIZE
local_discourse/app             latest              a779708720a4        2 months ago        2.68GB
discourse/base                  2.0.20190906-0522   6da16759d83d        3 months ago        2.29GB
discourse/base                  2.0.20190625-0946   2b3a5b47565f        6 months ago        1.93GB
discourse/base                  2.0.20190505-2322   ed87227f60d2        7 months ago        1.91GB
discourse/base                  2.0.20190217        9c24db193c37        10 months ago       1.92GB
discourse/base                  2.0.20181031        ea31cd77735a        13 months ago       1.88GB
discourse/base                  2.0.20180802        d6f8b6029227        16 months ago       1.74GB
discourse/base                  2.0.20180717        3af2eb204be0        17 months ago       1.71GB
discourse/base                  2.0.20171231        3925ef3919cc        24 months ago       1.73GB
discourse/base                  2.0.20170728        184b98f3b1d2        2 years ago         1.81GB
discourse/base                  2.0.20170531        4aa3fe49ae44        2 years ago         1.66GB
discourse/discourse             1.3.10              1881a9bd3afd        2 years ago         1.54GB

Surely not all are still needed, right? If I wanted to keep just the bare minimum, could all the discourse/base and that last discourse/discourse image be pruned?

I’m confused about the different image names local_discourse/app, discourse/base, discourse/discourse …

Could someone experienced provide a general “housekeeping” howto for keeping only the last, say, 3 images? I’m not a docker expert …

Try:

./launcher cleanup