Tech Challenge

$ docker ps -a
NAMES     STATUS            IMAGE
web       Up 3 days         nginx:1.25
old-job   Exited (0) 6 days busybox:latest

$ docker images
REPOSITORY   TAG       IMAGE ID    SIZE
nginx        1.25      a1b2c3d4    187MB
myapp        v1        e5f6a7b8    412MB      # no container uses it
<none>       <none>    99aabbcc    338MB      # dangling

$ docker volume ls
DRIVER    VOLUME NAME
local     pgdata          # mounted by web
local     archive-2024    # not mounted by anything

$ docker system prune -f