containers

The question that separates people who have debugged a hung rollout from people who have read about one. The interesting half is not the signal, it is PID 1.

A registry stores repositories, which hold manifests, which point at content-addressed blobs. Candidates who can draw that hierarchy and the auth dance around it understand every pull failure they will ever meet.

Fork failures can reflect PID limits or memory allocation failure even when host RAM looks available. Find which ceiling broke, cap PIDs per cgroup so one team's leak costs one pod, and fix the unbounded spawn.