Fedora 16: dropping spontaneously into "Emergency Mode"

['Chris Hall']

Having recently installed Fedora 16, replacing Fedora 14, I am now plagued by the thing spontaneously falling into "Emergency Mode"... "Welcome to Emergency Mode" ha ha !

The last things in /var/log/messages are:

Apr  7 14:55:54 hestia systemd[1]: Job dev-sdb5.device/start timed out.
Apr  7 14:55:54 hestia systemd[1]: Job local-fs.target/start failed with result 'dependency'.
Apr  7 14:55:54 hestia systemd[1]: Triggering OnFailure= dependencies of local-fs.target.
Apr  7 14:55:54 hestia systemd[1]: Found ordering cycle on sysinit.target/stop
Apr  7 14:55:54 hestia systemd[1]: Walked on cycle path to systemd-tmpfiles-clean.service/stop
Apr  7 14:55:54 hestia systemd[1]: Walked on cycle path to systemd-tmpfiles-clean.timer/stop
Apr  7 14:55:54 hestia systemd[1]: Walked on cycle path to sysinit.target/stop
Apr  7 14:55:54 hestia systemd[1]: Breaking ordering cycle by deleting job systemd-tmpfiles-clean.timer/stop
Apr  7 14:55:54 hestia systemd[1]: Job back\x2droot.mount/start failed with result 'dependency'.
Apr  7 14:55:54 hestia systemd[1]: Job fsck at dev-disk-by\x2duuid-8f6c18e2\x2d4b0d\x2d4602\x2db084\x2d29639bd6e173.service/start failed with result 'dependency'.
Apr  7 14:55:54 hestia systemd[1]: Job hestia.attic.mount/start failed with result 'dependency'.
Apr  7 14:55:54 hestia systemd[1]: Job dev-sdb5.device/start failed with result 'timeout'.
Apr  7 14:55:54 hestia rsyslogd-2177: imuxsock lost 114 messages from pid 973 due to rate-limiting
Apr  7 14:55:54 hestia ntpd[973]: ntpd exiting on signal 15
Apr  7 14:55:54 hestia kernel: Kernel logging (proc) stopped.
Apr  7 14:55:54 hestia rsyslogd: [origin software="rsyslogd" swVersion="5.8.7" x-pid="1022" x-info="http://www.rsyslog.com"] exiting on signal 15.

As it happens, /dev/sdb5 is a back-up partition... so is not in use most of the time... so (assuming this is the trigger for the system falling over) I don't know why it was suddenly felt to be essential to be able to start it... it is mounted when the system is booted.

The other suspicious character is ntpd to whom somebody has sent a SIGTERM and who appears to have sent a lot of "stuff" to the logging, which is nowhere to be seen :-(

Can anybody point be in the direction of what is going on here, and how I may be able to restore some stability to my Fedora 16 installation, which is currently falling over about once a day at random.

Thanks,

Chris