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

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9
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4answers
2k views

Choosing the right AWG for Server Power Cables?

When getting power cables for servers, there are are various AWG (American Wire Gauge) choices to make. The ones I have noticed are 18 and 14. 14 is thicker so will be a little more stiff. But I am ...
0
votes
1answer
61 views

Why would Windows 2008 lose its backup schedules at shutdown?

We recently powered down a Windows 2008 server for a weekend as the building power supply was being worked on. Right up until this shutdown, the backups have been happily running daily every day ...
0
votes
2answers
129 views

unexpected server power off

Once or twice per day I find a server I have powered off with no apparent reason. Info and what I've done until now: Nothing is being reported under /var/log/. Just normal server activity and then ...
1
vote
2answers
77 views

POE and AC power

Could there be any issues having both POE and AC power attached to a WAP? I'm curious because I found a few WAPs that had both...wondering if I should pull AC or just let it ride?
-4
votes
2answers
120 views

What's the deal with using unreliable green energy in datacenters? [closed]

The news say that Google now uses 48 MW of electricity produced by wind turbines to power one of its datacenters. I've always heard that "green" energy is great, but it is unreliable - wind doesn't ...
0
votes
0answers
24 views

Server only powers (but doesn't POST) when IDE drive is powered

So after a thunderstorm last night which did a little damage, a Gigabyte server has decided it's going on power on but not POST. If it is POSTing, it's doing a very bad job at telling me. No beeps, ...
0
votes
3answers
170 views

Power-over-Ethernet: Designing PSD with less than 48V?

I want to use Power-over-Ethernet for an IP Camera. On the host-side, which also is the PSE (Power Sourcing Equipment) I have my own hardware. On this hardware I just have 12V of supply voltage. ...
9
votes
2answers
2k views

How can I calculate if a UPS is sufficient for my requirements?

I am not that of an electricity knowledgable person, so I'll try to put as much info as possible. I have a Rack Mount UPS of 1800 Watts Model: PRP 3050 RM (in total I have 2 of these - talking about ...
7
votes
3answers
572 views

Source of PDU De-Rating?

In researching PDU's I have noticed most cite a derated current at the 80% level. For example, 30A is derated to 24A: Tripp Lite: Raritan: Does anyone have anything that shows what agency this ...
1
vote
2answers
191 views

Power-over-Ethernet: 100 Mbps Device compatible with 1 Gbps Source?

I have an IP Camera, which is supports Power-over-Ethernet. The relating Ethernet Switch on the camera supports 100Mbs. Now when I want to support the camera with Power over Ethernet, will it be ...
2
votes
1answer
121 views

Correct UPS and PDU sequence

I'm pretty inexperienced when it comes to setting up power for a network rack. I have a location that has a dedicated 20 amp circuit with a LP-20P socket. I have a APC UPS 3000XL rackmount UPS and a ...
1
vote
1answer
355 views

Self-Resetting Power Strips? [closed]

We are about to deploy a number of secure kiosks into an environment where they may be prone to lightning strikes and power surges on a somewhat regular basis (southern Florida in a place where the ...
0
votes
1answer
98 views

Metered-By-Outlet-Monitoring PDU [closed]

I see APC offers Metered-By-Outlet PDUs, however they only offer 30A - 32A 208V PDUs. (URL: http://www.apc.com/products/family/?id=478) We are looking for a 16A 120V PDU that offers power usage ...
0
votes
5answers
202 views

interference between redundant power supplies

I have a number of dell servers and two UPS. I plan to give two different input to servers from two different UPS, my question is: A short circuit of redundant powersupply unit (PSU1) will trip one ...
1
vote
4answers
3k views

Power Usage via IPMI or BIOS or?

Is it possible to check the power usage of an entire machine via IPMI, BIOS, or any other option? I have done some searching but no results have came up yet. PDUs only show the total usage, so this ...
1
vote
1answer
126 views

Power surge protection on office LAN, medium-small scale [closed]

I've got an office LAN setup with about 15 computers, which is due to expand to 30 before long. Each computer is on its own voltage stabilizer and UPS. I live in a place with horrible, substandard, ...
3
votes
2answers
279 views

Wattage Per Square Feet as a Measurement

I am used to looking at collocation providers where in U.S. are given as AMPs per rack (assuming 120V). I am looking into a place that rents space for servers which is listed as: "250 Watts per ...
5
votes
4answers
3k views

When do I need to consider 3 phase power? [closed]

Ok, I'm trying my best not to make this too subjective and provide all the information I can and if you can help make this a better question then please suggest. My friend an I have a small software ...
4
votes
3answers
578 views

How to properly configure power redundancy for devices with only one power input?

Some devices, such as servers and high-end switches have dual PSUs/power inputs, which can then be hooked up to separate UPSes, which are hooked up to separate power circuits (correct so far, right?). ...
1
vote
1answer
461 views

Upgrading memory on an IBM Power 710 Express (8231-E2B)

We have a Power 710 Express server that was loaded with 4x4 GB memory on a single riser card. I have replaced the 4 chips with 4x8GB and put in another riser card and loaded it with 4x8GB more for a ...
0
votes
3answers
2k views

Rackspace - typical power for a server

I'm trying to get some rackspace and buy an appropriate server. I've got a quote for 1/4 cabinet which includes 0.5kw of power. How do I know how much power my server will use...(e.g. I've looked on ...
5
votes
1answer
215 views

Using Y split cables to connect two servers to a single PDU receptacle

We have bought a few 30amp 208v PDUs that only have 9 receptacles. The servers we are connecting to those PDUs will not use the full 30amps (at 80%, or actually 40% since we use redundant power) so we ...
12
votes
4answers
618 views

Hooking up many different external HDs simultaneously

I need a large amount of external storage for an upcoming project. I'm planning on purchasing 10 2TB external drives. I need them all hooked up to a single machine at the same time. What issues ...
9
votes
2answers
1k views

How to check CentOS 6 Server VM Host after a power falure?

This afternoon, someone at our office decided to pull the plug out of our server because it was storming outside. They didn't shut it down, they just pulled the plug out while it was running. The ...
-2
votes
1answer
43 views

Disks online through power pull, replace? [closed]

Suppose you had a server cabinet and the power was pulled on the whole thing (this just happened to us). Now suppose you had a hard drive (3.5" SATA WD Enterprise) that was not previously in use. It ...
0
votes
1answer
313 views

APC switched PDU rack, lost state after reboot or power loss

I have the following: We have a few APC 7920 PDU's Using POWER IQ to control the PDS's via SNMP 1/2 Using also Mobile Power IQ to control the PDU if need via iPad/iPhone I am in the process of ...
2
votes
2answers
2k views

Virtual machine lost after power cut

We have just had a power issue and our ESX (ESXi 4.1.0) host lost power and then rebooted. All but one of the virtual servers have rebooted with no problem, however one of them refused to power up. I ...
7
votes
2answers
386 views

Green-IT: How do you deal with poweroff systems in your system monitoring?

Many of you probably have completed or are contemplating Green-IT projects with the goal to power off idle or unneeded systems when demand for computer resources is low: How you did handle this ...
4
votes
2answers
1k views

Does unbalanced load on three-phase UPS use more power and cost more?

We have a three-phase online data center UPS. Someone said recently that if the input amperage across the phases were 70-10-10 we'd pay for the kWh represented by 70 amps, but if the same load were ...
12
votes
5answers
1k views

Why is it important to ensure equipment is well-grounded?

I am installing a new ethernet switch, and the instructions say to connect the ground screw to the rack or some other kind of electrical ground. What are the risks of not ensuring that equipment is ...
3
votes
3answers
2k views

How to measure server power consumption?

We have data center running more than 2000 servers. We are planning to shutdown the servers on a weekend for cost cutting purpose. How can we calculate which servers are consuming more power in the ...
1
vote
4answers
18k views

Windows 2008 Server R2 turns itself off

I have a Windows 2008 R2 Server that switchs off on his own. and it does not look like a hardware problem since I can see in the log how all services are stopped and after: Log Name: System ...
1
vote
1answer
71 views

How much power draws a system like this idling in BIOS? [closed]

Let's assume a generic system like this: Two modern multi-core CPUs, like a Xeon Dual Core 2x 7120M, 3.00 GHz, 95 W power dissipation each, according to Wikipedia 2x 835Watt PSU (redundant) 8GB RAM ...
11
votes
2answers
1k views

Using 48v for servers

I'm currently in the middle of a process to specify and design a new server environment for graphics and video rendering. We know we want to use blades, and we're pretty sure of our vendor decisions. ...
3
votes
5answers
801 views

A plan to mitigate PDU failures?

A client just experienced a complete failure of an APC AP7911A switched/metered rack power distribution unit (PDU). This obviously took all of the connected equipment down with it. The equipment is ...
1
vote
3answers
110 views

USB Legacy support burning PSU, is it possible? [closed]

So one day, the PSU in the machine I was working with decided to blow up. Yes, I heard a pop, and a strong burnt smell. So what happened? What caused it? How can I prevent it? The situation: The ...
0
votes
1answer
78 views

How does a server power supply withstand unto toggling the power?

My server will run only weekly for 2 hours for backup purposes. After I finished the backuping I pull out the power plug from the power outlet. How does a server power supply withstand unto toggling ...
3
votes
1answer
1k views

What is the proper power cord for the usual rackmount server?

I'm trying to clean up a rackmount power environment, and wanted to check on the power cords. Currently, it seems that what I would consider to be appropriate are labeled mostly as 14AWG: 14AWGX3C ...
1
vote
2answers
480 views

How to put laptop to sleep with powershell/vbs/wmi/…?

I'd like to be able to put my laptop to sleep from the command line. According to Microsoft, the Win32_Battery WMI class has a SetPowerState method that looks like it should be able to do this, ...
2
votes
1answer
157 views

Monitoring power usage (AMPs/kWh)

Sorry if this is too near 'shopping' but after much Googling I've not really found any decent solutions. What I'd like to do is monitor the power usage, particularly AMPs and kWh/day used by a plug ...
6
votes
4answers
5k 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 ...
2
votes
1answer
152 views

PDU With Configurable AMP Limit

I have a 20 AMP/120V circuit. The only device plugged into this circuit is a 1000 Watt Dell UPS. Right now several devices plug directly into the 1000 Watt UPS. I wanted to order a PDU to help ...
10
votes
3answers
395 views

Should pcs be unplugged before restoring power

We have an upcoming scheduled power outage for maintenance. UPS protects our servers. But it has been suggested that all PCs should be unplugged to prevent damage from power surges when power is ...
2
votes
2answers
483 views

A/B Power Configuration for Server Cabinet

I'm upgrading our cabinet at our colocation for A/B power and wanted input on which of our options are good or bad. First, a bit of an overview of our setup: We currently have a single circuit feed ...
0
votes
1answer
366 views

Server/Power supply AMP usage

I've been looking into getting some servers with co-location, I've worked with co-lo'd servers before but this is the first time I've actually a rack up. All co-lo' providers specify a limit on the ...
3
votes
2answers
299 views

Power reading 2 amps with 13 servers?

We have a rack in a data center and we became suspicious of running out of power. But our power bar says 2 amps! It has a live indicator, so it's not just one reading. Do you think there's something ...
2
votes
1answer
399 views

Actions to take during/after a power outage

We're in the process of replacing the shelving in our server room, and I found a piece of paper that had been covered over which lists various actions to take during/after a power outage: ADSL modem ...
2
votes
2answers
3k views

APC Smart-UPS Amps - How many amps does it use all by itself?

APC Smart-UPS XL 3000 http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=su3000rmxl3u&tab=models I have two of these APC units. They use NEMA L5-30P electrical plugs. I'm ...
1
vote
3answers
1k views

Is it possible to use mixed 110V / 208V power on a single server with dual power supplies?

Is it possible to run a dual power supply server with one PS plugged into 110V, and the other power supply plugged into 208V? We've asked the vendors and they say they've never tested it or some other ...
-1
votes
7answers
354 views

How can I power down my server when the mains power plug is pulled out?

I have a server (Dell R310) running which has a main power cable (long) connected to power(in the wall). Anyone who is bored will pull out that cable (Train station/Airport/ Public zone) and server ...