I hit this bug too with Ubuntu 18.04. On boot sssd fails to find AD servers from DNS and then continues to query 127.0.0.1 port 53, which will never answer. The log looks like this:
(Wed Oct 10 13:04:13 2018) [sssd[be[ad.helsinki.fi]]] [resolv_getsrv_send] (0x0100): Trying to resolve SRV record of '_ldap._tcp.helsinki._sites.ad.helsinki.fi' (Wed Oct 10 13:04:13 2018) [sssd[be[ad.helsinki.fi]]] [resolv_discover_srv_done] (0x0040): SRV query failed [11]: Could not contact DNS servers which does not help much, since it doesn't mention the non existing DNS server (127.0.0.1) in the logs (you need to run strace to see it). Restarting sssd makes it go back online. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1723350 Title: sssd offline on boot, stays offline forever To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/sssd/+bug/1723350/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs