John R Pierce wrote:
Robert Arkiletian wrote:
On 3/10/08, nate centos@linuxpowered.net wrote:
You can turn on write back caching if you have a UPS as well (provided your UPS is wired into your system for a graceful shutdown)
Hopefully you have a redundant PS unit. Having a UPS is not going to help if your PS fails.
redundant power supplies connected to redundant UPS's. I've seen more UPS failures than I've ever had failed PSUs on proper server grade hardware.
Exactly - You can expect a UPS to need new batteries every few years, but I had one machine with a 4+year uptime (and only because I was able to move power cords, change UPS's, and swap it's mirrored hard drives on the fly). The machine is still running (RH 7.3) but it's less critical now and I was too lazy to drag along a UPS when I had to move it to a different location.