Power is required for all our servers, desktops, and other electronic devices to operate.

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28
votes
9answers
14k views

UPS and power strip interactions?

Sometimes I hear that you shouldn't plug (UPS brand X / any UPS) into (power strip brand X / any power strip) because of some interaction leading to poorly conditioned power, reduced battery life, ...
7
votes
8answers
21k views

VMware ESXi shutdown triggered by APC UPS connected via USB

I am shipping a bunch of ESXi 5.1 servers to remote offices where they will be powered via APC UPS. I would like to have the UPS trigger a shutdown of the connected server - I would then rely on the ...
6
votes
4answers
6k views

How to wake a server after UPS Shuts it down when Mains power is restored?

I have several Linux servers connected to APC UPSs. They are connected to the UPS via USB and configured to shutdown if the UPS sends a signal that mains power has been lost and has not returned after ...
185
votes
14answers
7k views

What is this very short power cable called?

I have a couple of networking components in my rack that take giant AC adapters ("power bricks") that don't fit neatly into my rackmount PDU. I have one "thingy" that is shown below, and I need to ...
54
votes
14answers
2k views

Is UPS worthwhile for non-production equipment? [closed]

Over the years, I've had to throw away a quite a few bits of computing equipment (and the like): Several ADSL routers with odd symptoms (losing wireless connections, losing wired connections, DHCP ...
32
votes
9answers
17k views

Does CPU power management affect server performance?

I was doing some simple hand benchmarking on our (live) database server during non-peak hours, and I noticed that queries returned somewhat erratic benchmark results. I had enabled the "Balanced" ...
23
votes
3answers
2k views

How do servers with redundant power supplies balance consumption?

I have several servers from the HP DL360 line (generations 5-8). Each of these servers has two power supplies installed. The 2 power supplies in each server are fed from different circuits. My ...
42
votes
7answers
7k views

Why do we still use power supplies on datacenter servers?

Computers mainly need three voltages to work : +12V, +5V and +3,3V, all of them are DC. Why can't we just have a few (for redundancy) big power supply providing these three voltages to the entire ...
6
votes
6answers
620 views

Data Center Design and Preferences

When either selecting a data center as a co-location facility or designing a new one from scratch, what would your ideal specification be? Fundamentally, diversified power sources, multiple ISPs, ...
12
votes
4answers
592 views

Is there any value in protecting both rack power feeds with their own UPS?

I've done some looking and have not found a satisfactory answer to this question. When is it necessary or suggested to use an independent UPS (on it's own mains branch circuit) for each power feed to ...
8
votes
2answers
251 views

“Zinc Whisker” issues?

Good morning; We've been having intermittent power supplies failures in our data center that have been preliminarily attributed to "zinc whiskers". I'm just starting to read about them (I just ...
1
vote
3answers
2k views

Data Center Power Draw Calculation

I have a difficult time calculating the power draw of our upcoming server (Dell R710) and what that means in terms of how a data center will calculate power costs. Hopefully you can help shine some ...
9
votes
4answers
555 views

Maxing out both PDUs in a rack with redundant power

If I have a rack full of servers using redundant power supplies, and I'm keeping the amps at 80% (16A of 20A), isn't this still asking for trouble in the event of a power loss on one of the circuits? ...
6
votes
2answers
14k views

ipmitool - can't find /dev/ipmi0 or /dev/ipmidev/0

Based on a previous question, I installed ipmitool (yum install ipmitool). Even after a reboot, though, i get the following error when trying to run ipmitool power status: Could not open device at ...
4
votes
1answer
2k views

PDU says to ground to rack with “thread making screw”.. this is impossible?

I'm trying to use the 'thread making screw' to ground my Dell PDU to the Rack, however the metal on the rack is impossibly hard. Is this even required? The included screws don't even seem "thread ...
3
votes
5answers
2k views

How can I troubleshoot a broken on/off switch?

I have a file server that was recently relocated in a transoceanic move. It isn't under warranty, as it was a custom-built in-house tower. When I hooked everything up and tried to boot it, the system ...
5
votes
2answers
172 views

Power on machine when there is power?

Is there a solution for powering a machine back on after power loss once the power is back on? I could use wake-on-lan, but if there is a solution (software or hardware) to automatically power-up once ...
4
votes
1answer
189 views

Heat generated by a HP ProLiant DL380p Gen8 entry EU servers

I have to buy a stand alone server rack to be placed in a machine room. The temperature can reach 30°C in the room (I have no choice with regards to the location). In order to correct for this I will ...
3
votes
2answers
430 views

Best practice on Linux servers and CPU/power throttling?

I am running a couple of Debian 6 (2.6.32) and 7 (3.2) Linux servers and all of them have energy saving settings enabled in their BIOS. Furthermore Linux shows that the CPUs are throttled if the ...
2
votes
1answer
703 views

Will a 20 Amp Circuit Work for 2 servers with 2 PSU ea. needing 9.2 Amp Input Requirement per PSU?

I'm a bit new to the power calculations for electricity at a colocation facility. I have 2 HP DL580s that are pretty maxed out and this is what the HP power calculators gave me for each server. Total ...