Server Power Usage

[herme3]

I purchased an IBM System x3400 7975 server, and I can't find very much information about its power usage. It has two power supplies, and I have them both plugged in at the moment. Here is what the instruction manual says in the server specifications:

 

One of the following power supplies:

 

*One nonredundant 670 watt (90-240 V ac)

 

*One 835 watt (90-240 V ac)

 

Note: Two 835-watt power supplies provide redundancy in hot-swap models; therefore, you must install an additional redundant power and cooling option kit (the option kit comes with an 835-watt hot-swap power supply and three hot-swap fans) to upgrade to redundant mode.

 

The way this is written seems very confusing. It says that the server has "one of the following power supplies", yet mine came with two. Does this mean that the second one is redundant, or would an optional third one be redundant?

 

Also, does the wattage refer to the amount of input required continuously, or is that the maximum that the server can output to the hardware components? The server can support two Xeon Quad-Cores and eight hard drives, but I only have one Xeon Quad-Core and two hard drives installed.

 

I'm looking for a battery backup, but many of them have an output limit of 300 or 500 watts. Would I need a more powerful backup for this server?

 

I've read all the documentation and searched on Google, but I can't find very much information about this server's power usage. If anyone can offer advice, I would really appreciate it. Thank you.

[Cap'n Refsmmat]

Your power supplies are redundant only if both are plugged in. The 835 watt number is the maximum power the supply can handle before frying, not the amount the computer would use. And yes, you would need a better backup battery.

[herme3]

Hi Cap'n,

 

Thank you for the information. So, I only need to have one of the power supplies plugged in? Also, what type of backup battery would you recommend? I was looking at APC's web site, and they have many different sizes and types. I would like to have several hours of backup power, but many of those only support 300 watts.

[Cap'n Refsmmat]

You only need to have one power supply plugged in, as far as I know. I'm not sure about the battery; it would probably have to be one of these doodads. Poke around here and see what fits your budget.

[insane_alien]

you can buy small power meters(they're really ammeters with a different scale) that plug into the wall socket and you plug the server into that.

 

that will give you the true power usage. you might want to take it from under a heavy load since if you are moving to battery backup you generally just want to save everything and shutdown before you lose something. that puts a bit of strain on the server. if you want continuous usage though, just check you have enough battery to run for a few hours and set it up to shut down when the battery gets low.

[herme3]

I appreciate everyone's suggestions. Do you think this one would be good: http://apc.com/resource/include/techspec_index.cfm?base_sku=SC1500&total_watts=25

 

It would be nice to have a longer backup time, but it seems to be the best one under $500.

[insane_alien]

thats about the best you can hope for at those prices. even if you do have time to spare, you're still looking at a shutdown ASAP scenario. you don't want to get even close to the limit. if the hardware on your server supports it you might want to look at forcing it to go into a low power mode to give you even more leeway.

[herme3]

One advantage of this UPS is that it includes a version of the PowerChute program that works with Linux. Will this perform a graceful shutdown and prevent data corruption?

[insane_alien]

dunno, never used it before.