long-lived-negative-dns-cache

A long-running process (a cron supervisor, a daemon, a worker pool parent) caches a NEGATIVE DNS result after a transient network blip and then never retries, so every downstream call fails forever even though the network recovered seconds later. A wrapper bug can log a fake exit=0, hiding it. Symptom: 'nothing runs anymore' with no error. Fix: restart the process, then bound the DNS/connection cache TTL.