- Bug: device departs → timer starts, but last_departed_time not set yet
If device re-arrives before timer fires, timer never cancelled
Result: false DEPARTED alert sent after re-arrival debounce expires
- Fix: Cancel any pending departure timer immediately on re-arrival,
before checking last_departed_time
- Test: Added regression test that verifies timer is cancelled when
device re-arrives before 15-min debounce expires, preventing false alerts
- All 10 tests passing
- Infrastructure IPs (gateway, self, broadcast) silently ignored in
on_arrival() and on_departure(); seeded at startup from 'ip route'
- 15-minute departure debounce: alert only fires if device is still
absent after 900s, eliminating ARP cache flush false positives
- 5-minute re-arrival suppression: ARRIVED alert skipped when device
returns within 5 min of a recorded departure (covers interface flap)
- DHCP renewal dedup: known device re-announcing within 30 min skips
ARRIVED alert
- Tests added for all four suppression paths (9 total, all passing)
- Replace broken OUI file lookup with inline dict of 200+ common vendors (works on Armbian)
- Fix hostname/IP duplication when reverse DNS fails (show IP once, not twice)
- Add format_arrival() and format_departure() helpers for consistent alert formatting
- Update on_arrival/on_departure to use new formatting functions
- Add comprehensive tests for hostname dedup and OUI lookup
Cobra