The System View

Asking the Engine About Itself

$ docker info            # daemon config: storage driver, cgroup version, runtimes
$ docker system df       # disk usage: images / containers / volumes / build cache
$ docker events          # live stream of everything the daemon does
$ docker version         # client AND server versions (they can differ!)

docker system df is the first command on any "disk full" incident:

TYPE            TOTAL   ACTIVE  SIZE      RECLAIMABLE
Images          24      3       6.2GB     5.1GB (82%)
Containers      31      2       890MB     870MB (97%)
Local Volumes   12      4       2.3GB     1.8GB (78%)
Build Cache     204     0       3.4GB     3.4GB

docker events is the daemon's flight recorder - during an incident, run it in a second terminal and watch kills, OOMs, restarts and health transitions happen in real time:

$ docker events --since 30m --filter type=container --filter event=die

Tip: Storage locations worth knowing: images and container layers live under /var/lib/docker, one reason that directory (or its Docker Desktop VM equivalent) grows - and why pruning is a real operational task.