Re: Cutting power without breaking RAID

[Tim <irule@irule.net>]

Your UPS won't accept a timer value to wait before actually cutting
power? That would probably be ideal, issue the power off command with
something like a 30 second timeout, which would give the system time to
power off cleanly first.

-Tim

Niccolo Rigacci wrote:
> Hello,
>
> I'm facing this problem:
>
> when my Linux box detects a POWER FAIL event from the UPS, it 
> starts a normal shutdown. Just before the normal kernel poweroff, 
> it sends to the UPS a signal on the serial line which says 
> "cut-off the power to the server and switch-off the UPS".
>
> This is required to reboot the server as soon as the power is 
> restored.
>
> The problem is that the root partition is on top of a RAID-1 
> filesystem which is still mounted when the program that kills the 
> power is run, so the system goes down with a non clean RAID 
> volume.
>
> What can be the proper action to do before killing the power to 
> ensure that RAID will remain clean? It seems that remounting 
> the partition read-only is not sufficient.
>
>