Keeping tradition with doing things backwards, I've finally got a UPS for the rack (mounted in the bottom of the stack). Got a PowerWalker VI 2200R. Its a 2U unit which is all the space I've got left in the rack. Decent price and decent I/O with USB, serial and a slot-in for network expansion + 4 IEC outputs. Its powering everything in the rack and connected via USB to my main server which runs a NUT server that other machines can connect to. A calibration run (100-80%) puts the runtime at about 20 min. Long enough that I'm comfortable setting things to shut down when 20% capacity remains. Summary, I sleep better now.
Great setup! I’ve heard that it is best practice to keep a little distance between servers/drives and the UPS just to be safe from vibrations or EMI. Does anyone know if this is still something to worry about?
What in your UPS is vibrating? You mean the fans?
no clue, mine doesn’t seem to vibrate. just one of the things that popped up when I searched for why they used to warn against it. was hoping to get a “back in my day” comment explaining why.
Back when I built racks, our "standard" was UPS at the bottom, all drives at the top...but mainly for accessibility. Hadn't even thought about vibrations or interference!
Ups at the bottom is also because of the weight of the batteries. In a small rack like this I don't think moving the disks 30cm up will make a big difference.
Absolutely on that point. Same goes for heavy multi zone amplifiers.
Man I loved building racks. Almost makes me miss field work...
Drives at the top? Hell no. SANs are heavy, they go in the bottom half too (assuming a mixed rack). Especially if you have those disk shelves that slide out so they hold 3.5" drives three deep. Top of the rack is for network hardware and such.
I did not install SANs, I built racks for AV so the only drives were NAS/mini PCs on shelves
If there were ones that vibrated or had interference enough to affect neighboring units, that would be marketing points. As it is now, no one mentions any of those points. It’s all capacity, I/O and features.
If there were units that showed any of those issues, the reviews would tell.
This unit is basically dead silent in normal operation. During charging and discharging there is an audible hum, but nothing else. I haven’t noticed any vibration or ZFS scrubs reporting corrections.