Always detect network changes (LAN IP, upstream, peers) regardless
of upstream config. LAN IP is now tracked in ServerCtx and updated
every 30s — multicast announcements use the current IP instead of
the startup IP. Upstream re-detection still only runs when
auto-detected. Peer flush triggers on any network change.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Upstream DNS was resolved once at startup and never updated. Switching
Wi-Fi networks made all queries fail until restart.
Now spawns a background task (every 30s) that re-runs system DNS
discovery and swaps the upstream atomically if it changed. Also flushes
stale LAN peers from the old network on change.
Only activates when upstream is auto-detected (not explicitly configured).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Replace IP-based self-announcement filtering with a per-process instance
ID (pid ^ timestamp) so multiple instances on the same host can discover
each other. Enable SO_REUSEPORT for multicast socket binding on Unix.
Add multicast address validation on configured group.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Numa instances on the same network auto-discover each other's .numa
services. No config, no cloud — just multicast on 239.255.70.78:5390.
- PeerStore with lazy expiry (90s timeout, 30s broadcast interval)
- DNS resolves remote .numa services to peer's LAN IP (not localhost)
- Proxy forwards to peer IP for remote services
- Graceful degradation if multicast bind fails
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>