netinfra-02 now advertises exit node routes (0.0.0.0/0, ::/0) in
addition to the subnet route, matching netinfra-01's configuration.
Both nodes are now fully redundant subnet routers + exit nodes.
Subnet route (192.168.0.0/22) is approved and active. Exit node
routes (0.0.0.0/0, ::/0) require separate approval in the Tailscale
admin console.
[#377]
Adds section documenting the redundant subnet router architecture:
both netinfra-01 and netinfra-02 now advertise 192.168.0.0/22 for
automatic failover. This fixes the SPOF where all remote monitoring
(Uptime Kuma on Cloudron VPS) routed through netinfra-01 alone —
any DERP bounce or Docker LinkChange event took down visibility to
every LAN host simultaneously.
Also documents the resolv.conf immutable flag fix on netinfra-01
(chattr -i) that was preventing tailscaled from updating DNS config
after every link change event.
[#377]