Further problems with systemd-resolved on xubuntu 17.04

[Chris Green]

Well, having bodged my domain name into /etc/resolv.conf it seems that
systemd-resolved is *still* somewhat broken.

When I start the system it can resolve local names OK but after a
while (I haven't quite determined how long it is yet, but somewhere in
the ten to twenty minutes area I think) it fails to resolve local
names, as before with SERVFAIL.

If I restart systemd-resolved then it works again.

The result of 'systemd-resolve --status' remains unchanged all the
time. 

Aha!  ... in /var/log/syslog I see:-

    Jun  7 08:29:22 t470 systemd-resolved[955]: Switching to fallback DNS server 8.8.8.8.
    Jun  7 08:29:33 t470 systemd-resolved[955]: Switching to DNS server 192.168.1.2 for interface wlp4s0.
    Jun  7 08:31:07 t470 systemd-resolved[955]: Using degraded feature set (UDP) for DNS server 192.168.1.2.
    Jun  7 08:35:54 t470 systemd-resolved[955]: Switching to DNS server 8.8.8.8 for interface wlp4s0.

So *why* does it switch to using 8.8.8.8, plus why does it give a
SERVFAIL message, surely it should be a not found error.


-- 
Chris Green