UPS Error

[Leon Shen]

Hi Experts,

There was an abnormal system shutdown by itself on 21/06/2005, ard 7.20pm. The messages which appear on console shown as below:-

“Console login:/usr/lbin/ups_mond: AC Power to all recognized, system critical UPS’s OK! System will not shutdown

/usr/lbin/ups_mond: UPS /dev/tty0p3 batter low

/usr/lbin/ups_mond : reboot –half invoked due to ups error cited in previous syslog message

/usr/lbin/ups_mond : UPS /dev/tty0p3 could not execute command s120 rro; return (actal 144) Syncing disk (12 buffers to flush):12

0 buffer not flushed
0 buffer still dirty

Closing open logical volume

Done

Console reset done

Based on above messages, could you tell me whether the system shutdown properly or not?
What should I do?

Best Regards

[Eknath]

HI Leon,

It looks like server was shutdown due to battery power low. Boot the server in single user mode and check if you can mount all the filesystems. If this is through without any error then 90% you dont have to worry.

Cheers!!!
eknath

[Bill Hassell]

The message:

UPS /dev/tty0p3 could not execute command s120 rro;

does not look right. Normally, the ups_mond program runs the command shutdown or reboot depending on the UPS configuration. However, the "syncing disks" and "0 buffer not flushed" indicates that the OS was indeed shutdown and the disks synced. NOTE: this does not mean that the applications were properly shutdown. Normally, shutdown -y -h 0 is used and the applications are shutdown in an orderly manner. If reboot is executed, all of this is bypassed, all processes are killed and the disks synced. For simple processes, this is OK. But for a database, you would want a normal shutdown. You'll need to contact HP about configuring the UPS for a normal shutdown.

Note: if this is an old UPS (that is, the batteries are more than 3 years old), then the battery voltage dropped too fast which is why reboot was run. ups_mond tries to pick the best method and if there isn't enough time to properly shutdown the system, it will issue reboot to at leasst protect the filesystem. Always schedule battery replacement every 3 years.