Just remember that batteries (in both RAID cards and UPSes) wear out and will eventually have to be replaced. It depends how critical your data is, but if you only have a UPS, you risk badness in the off chance that your power fails and you haven't replaced your UPS battery.
On Feb 27, 2007, at 12:27 AM, Peter Kovacs wrote:
I wonder if running a machine on a UPS + 1 hot standby internal PS is
equivalent, in terms of data integrity, to using battery backed write
cache. Instinctively, I'd think that UPS + 1 hot standby internal PS
is better, since this setup also provides for the disk to actually
write out the content of the cache -- as you pointed out.