# Diagnosis

*2026-10-02.*

**Located in `mesh-host` `internal/outward`.** `Links` read the kernel's routing tables and returned the
interfaces carrying a default route. An unplugged port carries none, so it was never reported, and the
controller rendered the filter around the links it was given.

**The fix.** A link faces outside if it carries a default route **or** has a physical device behind it.
The kernel lists every interface under `/sys/class/net`, with a `device` entry for one backed by
hardware. A bridge, a veth, the tunnel and the loopback have none, so they stay the machine's own. The
wired port is now reported up or down, and the filter guards it before anything is plugged in. Tested
with a radio carrying the default route and an unplugged wired port beside a bridge, a veth, the docker
bridge, the tunnel and the loopback: the two physical links are reported, nothing else.