James Pearson wrote: > > We are seeing a problem that occurs ~5% of the time when rebooting > CentOS 7.7 where systemd gets a 'Connection timed out' to D-Bus just > after the D-Bus service starts - from 'journalctl -x' : > > ... > Jan 21 16:09:59 linux7-7.mpc.local systemd[1]: Started D-Bus System > Message Bus. > -- Subject: Unit dbus.service has finished start-up > -- Defined-By: systemd > -- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel > -- > -- Unit dbus.service has finished starting up. > -- > -- The start-up result is done. > Jan 21 16:10:24 linux7-7.mpc.local systemd[1]: Failed to register match > for Disconnected message: Connection timed out > Jan 21 16:10:24 linux7-7.mpc.local systemd[1]: Failed to initialize > D-Bus connection: Connection timed out > ... We've managed to work out what the problem is - it is the same issue as given in https://bugzilla.redhat.com/show_bug.cgi?id=1531486 We have a legacy use of NIS for groups - which can cause a boot time deadlock: systemd->dbus->nis(glibc)->rpcbind->systemd A workaround is given in https://access.redhat.com/solutions/3900301 (account needed to view) - but it is just essentially reverting the changes made to /usr/lib/systemd/system/rpcbind.socket between 7.5 and 7.6 James Pearson