On our Ubuntu 18.04 servers, sssd won’t start. Logging shows that it can’t find any DNS
servers. Restarting sssd fixes it.
/etc/resolv.conf is a symlink to ../run/systemd/resolve/stub-resolv.conf
If I replace that with a hardcoded resolv.conf with the right name server, sssd comes up.
Network Manager replaces the file with a different one pointing to nameserver 127.0.0.53,
but after another reboot with that file it still works.
This happens on 4 identical servers, but not on a VM with the same OS. I assume there’s a
timing issue of some sort.