UPS For Server Cupboard

[dhicks]

Hello All,

 

I'm currently figuring out what work needs doing to our two server cupboards over the summer. The idea is that we have two cupboards, in separate wings of the school, so if something diasaterous happens to one then the other is left to keep running. This only works up to a point at the moment - the second server cupboard has no cooling and tends to get good and toasty, and the UPS didn't handle testing so well today ("Power's off, is stuff still running?", "No.", "Bother.").

 

I have environment monitoring sorted out - simply a PC with a temperature sensor and UPS-monitoring cable plugged in. It's set to turn itself off if running on battery for more than a minute or if the temperature gets too high, then I plan to have another PC monitoring that.

 

The UPS currently in use is an APC Smart-UPS 750. Simply switching the power off to it made the two machines attached to it fail, which makes it a bit pointless. Is that failure maybe just due to an aged bettery, or is there possibly a different brand of UPS that people would recommend?

 

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David Hicks

[ChrisH]

It will likely be the batteries. They look all nice and charged until you actually try to use them and they say not today thank you!

[3s-gtech]

We have an identical setup which I'm currently working on, responses will be interesting. I'd like a small air-con unit and UPS for the second cupboard, but may be a bit pushed!

[dhicks]

It will likely be the batteries. They look all nice and charged until you actually try to use them and they say not today thank you!

 

The monitoring software (APC's PowerChute Business Edition, monitoring the UPS via serial as USB failed to work for some reason) says the UPS has 23 minutes runtime left, however actual runtime is 0 (cut the power, everything stops). With the failed USB and dodgy readouts I'm inclined to get a whole new UPS - I don't want to get new batteries to find that the UPS still doesn't work reliably.

 

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David Hicks

[dhicks]

We have an identical setup which I'm currently working on, responses will be interesting. I'd like a small air-con unit and UPS for the second cupboard, but may be a bit pushed!

 

The cheap-as-possible temperature sensor from eBay is currently reporting a temperature of 31C - I've just borrowed a thermometer from science to double-check that's accurate. I'm guessing it's got a lot hotter in there in the past, though - there's only one server running in there now as the other one packed up, I think from overheating. I was maybe thinking of a floor-standing air conditioner capable of a "ton" of cooling (1200 BTUs, I think) - around £500 from Argos, which seems pretty resonable for an all-in-one, drop-in solution.

 

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David Hicks

[pete]

With the failed USB and dodgy readouts I'm inclined to get a whole new UPS - I don't want to get new batteries to find that the UPS still doesn't work reliably.

 

It'll require some downtime, but does the other UPS use the same batteries? It's a cheap test if it does - swap them for a test and give it a dummy load (stuff without data on) and see how well it fares.

[dhicks]

It'll require some downtime, but does the other UPS use the same batteries?

 

Good point, thanks. We've got a Smart-UPS 1000 and 1000XL in the other server cupboard, it's worth a check to see if they are battery-compatible.

 

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David Hicks

[SYNACK]

A smartUPS 750 is quite small for a two PC load let alone a two server one, it is probably the batteries but it could also very well be pulling too much current for the unit itself to supply when on battery power. I would be looking at a 1500 for a couple of machines just to give it the overhead, this should also give you longer runtimes for the servers in the case of a short powercut or something simmilar.

[dhicks]

A smartUPS 750 is quite small for a two PC load let alone a two server one

 

Good point - I think we're going to be maybe looking at the 2200. The cupboard will have at least four machines running in it: mirroring VM server, backup file server, video file server and environment monitoring PC, plus a network switch. Power only has to last long enough for the monitoring software to register the fact and gracefully shut everything down, so 5 to 10 minutes should be fine.

 

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David Hicks

[rsenior]

Hi Dave ,

Have look at this link :UPS Selector Sizing Applications

 

It will give you a good idea of what to buy load wise . We use r5000va on all of our server cupboards(most have 5 or more server +switches, etc) and they are excellent.Comes with temp. shutdown and web interfaced software. Always worth checking the load rate on the ups ,most of the larger units require a 30amp supply and you should have a clean earth on the cab.

[dhicks]

Have look at this link

 

Thanks, but a bit pricey for us - we might be able to stretch to a Smart-UPS 2200, but anything beyond that would be pushing it a bit.

 

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David Hicks

[VirtueTechnologies]

david

 

sory to jump on the thread - but if we can help you out in quoting for the UPS please do let me know.

 

kind regards

 

zak

[dhicks]

if we can help you out in quoting for the UPS please do let me know.

 

I'm trying to figure out what sort of size of UPS we're likly to be looking at, first. I think our second server cupboard is likly to wind up containing a server running a bunch of virtual machines, a large (12 SATA disks) file server and a smaller (4 SATA disks) file server. It will also contain a PC set up to monitor power and temperature, and there's a 16-port network switch, but those can run off a Back-UPS 350. Some room for future expansion would probably be a good idea. How much power are those three servers, some with lots of disks, likely to draw? Do I allow 1KW each for them, or is that being a bit excessive? What UPSes do you sell - just APC, or can you particularly recommend another brand?

 

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David Hicks

Edited June 17, 2010 by dhicks

[VirtueTechnologies]

Hello David

 

i think you approach is right its better to be safe than sorry.

 

This UPS should suffice, we always recommend APC for their reliability

 

SUA1500RMI2U

 

We also recommend a management card to allow graceful shutdown of all servers

 

AP9630

 

Maybe worth searching the web/APC website to get the specs for the above products.

 

regards

 

Zak

[SYNACK]

I'd look at the detailed specs of each of the bits that you are looking at using and seeing how much power it is likely to use Internal Hard Drive | Barracuda XT Desktop Hard Drive | Seagate | Seagate

 

I'd then double what you come up with for overhead and future expantion and aim for that. Most hardware will have current draw specs and if not just make an estimate on the generous side for the device. This is easier with some equipment from major manufacturers as there is are lots of load calculators that will help size the ups as have been suggested before.

[dhicks]

Most hardware will have current draw specs and if not just make an estimate on the generous side for the device.

 

The latter option is probably the best - I estimate we might have around 4,000W of power drawn, total, in that cupboard. Does that mean I simply need to get a 4,000VA UPS? I've tried that calculator linked to above, but when I input 4,000W it gives me a product priced at around £8,000, which is rather more than we can afford...

 

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David Hicks

[dhicks]

This UPS should suffice, we always recommend APC for their reliability: SUA1500RMI2U

 

Okay, thanks. I think we might need more than 1,500VA (does maximum power draw of server in Watts translate simply to VA rating of UPS?). Would it be better (and cheaper) to buy a single, larger UPS, or to use two of those 1,500VA devices? How much heat do they put out? How heavy are they - we don't have a proper rack in the cupboard, just a coffee table, which I don't think is going to be up to holding a UPS. Could they stand under the table on the floor?

 

We also recommend a management card to allow graceful shutdown of all servers

 

I currently have a PC with a cheap USB temperature sensor and a serial link to a UPS. If the power goes off or the temperature goes above a given limit for more than a minute then the PC turns off. I then have an application that pings that PC every minute or so - if it doesn't get a repsonse it uses SSH to shut down first virtual machines and then their physical hosts. What advantages does your management card offer over such a system?

 

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David Hicks

[richardp]

It really depends on what you want the ups to do I think. Do you simply want it to run long enough so that there is enough time to trigger and shutdown everything or do you want to run everything for X minutes in the hope the power will return or a generator will kick in? I would also recommend APC for their reliability which however does come at a price. Also some ups have a built in temperature sensor to monitor the environment for you, it all comes down to how much you have to spend as there is little point in looking at a high end ups at £10,000 when all you have to spend is £1000.

[dhicks]

Do you simply want it to run long enough so that there is enough time to trigger and shutdown everything

 

Yes, that's it - 10 minutes runtime is all that's required, really.

 

Also some ups have a built in temperature sensor to monitor the environment for you

 

Our current Smart-UPS seems to have an internal temperature sensor to measure its own internal temperature, which isn't quite as useful. If you mean an add-on management card then see above for question regarding management card vs. £5 USB temperature sensor from eBay.

 

there is little point in looking at a high end ups at £10,000 when all you have to spend is £1000.

 

Under £1,000 is more like it. How practical is making your own UPS out of car batteries?

 

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David Hicks

Edited June 17, 2010 by dhicks

[dhicks]

While we're dicussing server cupboards: just how flamable are computers these days - do you need fire supression? If so, will an automatic fire extinguisher as sold for boat engine rooms and similar be the most suitible thing?

 

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David Hicks

[dhicks]

we always recommend APC for their reliability

 

Just looking at the APC website and guide prices (I assume actual prices are a bit lower than this):

 

APC Smart-UPS 2200VA £589.00

APC Smart-UPS 2200VA 2U £829.00

APC Smart-UPS 3000VA £899.00

APC Smart-UPS 3000VA 2U £1,075.00

APC Smart-UPS 5000VA £1,925.00

 

Why are the 2U versions more expensive than the same capacity tower units? To get 4400VA of UPS power, should we simply spend £1,178 on two 2200VA tower units (27p per VA) instead of £1,925 on one 5000VA unit (39p per VA)?

 

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David Hicks

[dhicks]

Just looking at the APC website and guide prices (I assume actual prices are a bit lower than this)

 

Yes - Amazon have the SUA2200I for £460.

 

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David Hicks

[richardp]

I bought an APC SURT8000XLI approx 18months ago for a project for around £1500 on a special offer (ex VAT), having just had a look they seem to have doubled in price now. However this ups had to be wired into the mains supply on a new circuit which cost almost as much as the ups itself. This model comes with the management card and a separate temperature sensor module that you can place anywhere in your rack. I think the advantage of the management system over your PC with USB sensor is that its an all in one system, your not having to run an extra computer to achieve it and the software is probably a lot more flexible. I doubt anyone would recommend you try and build a ups out of car batteries either. :-) There is nothing wrong with your solution and if it allows you to protect your system within the budget you have then all the better.

[dhicks]

I think the advantage of the management system over your PC with USB sensor is that its an all in one system, your not having to run an extra computer to achieve it

 

Good point - does seem rather silly to run a whole PC who's job it is to stay switched on until something goes wrong.

 

and the software is probably a lot more flexible.

 

Well, no - the software is a Python script, which we can have do whatever we like. It needs to shut down VMs first, then physical servers.

 

I doubt anyone would recommend you try and build a ups out of car batteries either.

 

Sissies. No sense of adventure.

 

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David Hicks

[richardp]

Well, no - the software is a Python script, which we can have do whatever we like. It needs to shut down VMs first, then physical servers.

 

Yes sorry you are correct, it's been a long hot day, of course anything like a custom script will do anything and everything you want. I used to be in the same boat as you with a very small budget when I worked in the private sector and I remember having to come up with loads of cost saving solutions to problems, I sort of miss that a little bit and still find it hard to break the habit.

 

 

 

Sissies. No sense of adventure.

 

Ha ha true very true :-)