UPS / USB / system reboot

[Zbigniew Szalbot]

Hello,

I am running apcupsd. Toady we had several power failures. One of them
lasted longer than the UPS was able to sustain. So:

Mon Feb 18 15:21:06 CET 2008  Power failure.
Mon Feb 18 15:21:12 CET 2008  Running on UPS batteries.
Mon Feb 18 16:40:19 CET 2008  Battery power exhausted.
Mon Feb 18 16:40:19 CET 2008  Initiating system shutdown!
Mon Feb 18 16:40:19 CET 2008  User logins prohibited
Mon Feb 18 16:40:19 CET 2008  Attempting to kill the UPS power!
Mon Feb 18 16:40:25 CET 2008  UPS will power off after 180 seconds ...
Mon Feb 18 16:40:25 CET 2008  Please power off your UPS before
rebooting your computer ...
Mon Feb 18 16:40:57 CET 2008  apcupsd exiting, signal 15
Mon Feb 18 16:40:57 CET 2008  apcupsd shutdown succeeded

First of all, I am not really sure why it says to power off UPS before
reboot. It often happens that with power failuers there's no one
around.

Secondly, the system was unable to reboot, not sure but the culprit
seems to be this entry in fstab:

/dev/ad3s1d            /backup         ufs     rw              2       2

ad3s1d is a USB hard drive. It is normally unmounted and I think it
was unmounted while power failure occured. Why would it cause problem
while system is resuming operation?

Feb 18 16:40:25 lists apcupsd[493]: Please power off your UPS before
rebooting your computer ...
Feb 18 16:40:25 lists shutdown: halt by root: apcupsd initiated shutdown
Feb 18 16:40:57 lists rc.shutdown: 30 second watchdog timeout expired.
Shutdown terminated.
Feb 18 16:40:57 lists init: /bin/sh on /etc/rc.shutdown terminated
abnormally, going to single user mode
Feb 18 16:40:57 lists syslogd: exiting on signal 15

The result was I had to come to the site and fsck, then comment out
the /backup line in fstab. Only then the system was able to start.
Otherwise it complained about not being able to find /backup or the
like but I cannot now find the precise message in logs.

Your advice is greatly appreciated!

-- 
Zbigniew Szalbot