By default headscale fetches https://controlplane.tailscale.com/derpmap/default
at startup and treats failure as fatal, so it cannot boot when that URL is
unreachable. A self-hosted control plane that will not start without
Tailscale's infrastructure rather misses the point of self-hosting -- and
it crash-looped for exactly that reason while neptun had no DNS.
Enable the embedded DERP server on region 999 and drop the upstream map.
The relay rides Caddy on :443, which is why that vhost already sets
flush_interval -1; only STUN needs a port of its own.
Verified against headscale 0.28.0 before committing: it starts clean with
urls = [], registers "DERP region: {RegionID:999 ...}" pointing at
vpn.mgaction.town with DERPPort 443, and brings up STUN.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
darmanandClaude Opus 4.8
3671841eca