All three workers now share a run_health_heartbeat helper in
decnet.bus.publish. Each publishes system.<worker>.health on a 30s tick
with {worker, ts} plus optional per-worker extras. Subscribers can
watch system.*.health to see every DECNET worker on a host at once.
- agent: heartbeat runs inside the FastAPI lifespan alongside the
existing master-facing heartbeat; bus-disabled path is a no-op.
- forwarder: heartbeat task spawned at run_forwarder entry, cancelled
in the finally block so a crashed master loop never leaks the task.
- updater: new FastAPI lifespan hosts the heartbeat.
Heartbeat helper swallows extra() failures and is cancellation-safe so
lifespan teardown never hangs on it.
Worker-side log_forwarder tails the local RFC 5424 log file and ships
each line as an octet-counted frame to the master over mTLS. Offset is
persisted in a tiny local SQLite so master outages never cause loss or
duplication — reconnect resumes from the exact byte where the previous
session left off. Impostor workers (cert not signed by DECNET CA) are
rejected at TLS handshake.
Master-side log_listener terminates mTLS on 0.0.0.0:6514, validates the
client cert, extracts the peer CN as authoritative worker provenance,
and appends each frame to the master's ingest log files. Attacker-
controlled syslog HOSTNAME field is ignored — the CA-controlled CN is
the only source of provenance.
7 tests added covering framing codec, offset persistence across
reopens, end-to-end mTLS delivery, crash-resilience (offset survives
restart, no duplicate shipping), and impostor-CA rejection.
DECNET_SWARM_SYSLOG_PORT / DECNET_SWARM_MASTER_HOST env bindings
added.