On Debian systems, unless configured by something else, there isn't an
/etc/resolv.conf in the initramfs, which hinders DNS resolution.
Tailscale has its fallback DNS functionality, but that has problems [1]
in the corner-case situation of a Debian initramfs environment:
- no /etc/resolv.conf means tailscale (or golang?) attempts to use
127.0.0.1 as a DNS resolver
- the loopback interface (lo) isn't brought up in the initramfs. linux
sends the DNS traffic off-device (destined for 127.0.0.1)
Even with the Tailscale fix for that issue, it's a fallback and there's
a noticeable delay, so do the correct thing here and create
/etc/resolv.conf.
[1] https://github.com/tailscale/tailscale/issues/6110
564c3c3539