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>
