Add fallback DNS resolvers to all nodes

All nodes now list 1.1.1.1 and 8.8.8.8 as fallback nameservers after
MCNS. When MCNS is down, internal names (.svc.mcp.metacircular.net)
fail but external DNS (google.com, github.com, etc.) keeps working.

Lesson from 2026-04-03 incident: without fallbacks, MCNS failure
caused total DNS blackout including external services, forcing
Tailscale to be disabled to restore any DNS resolution.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
This commit is contained in:
2026-04-03 09:30:09 -07:00
parent 5a381d314e
commit 5d82e27ba4
4 changed files with 16 additions and 12 deletions

View File

@@ -22,8 +22,8 @@
networking.firewall.allowedTCPPorts = [ 53 443 8443 9443 8080 9090 ];
networking.firewall.allowedUDPPorts = [ 53 ];
# Route internal Metacircular zones to rift's own CoreDNS.
networking.nameservers = [ "192.168.88.181" ];
# DNS: MCNS for internal zones, public resolvers as fallback.
networking.nameservers = [ "192.168.88.181" "1.1.1.1" "8.8.8.8" ];
services.resolved.domains = [ "~mcp.metacircular.net" ];
};
}