What UPS do you have?

[Optimus_Primal]

HI

 

My school was rebuilt along side a neighbouring school (not in the same trust) by Civica in 2012. This site was originally designed to operate as the data centre for both schools until the leadership decided they wanted nothing to do with Civica and the contracts.

 

I have a pretty big UPS which is costing an arm and a leg to maintain PowerWAVE 9000 DPA 2x40kVA.

 

I am just wondering what others have, we have a 2 node cluster here.

 

Thanks

[Steve21]

Depends how long you're after really.

 

Ours is more for spikes/power loss, but we aren't expecting to run it for hours. A single APC 3000 model would more than do a 2 node cluster

 

Steve

[Optimus_Primal]

Its been put in to be able to keep the servers for two site going for a while but its now overkill and costing us alot.

I am the SLT for the area and doubling up as the network manager until we find a new one.

 

But even I know its too much.

[Steve21]

What do you call a while though... Bearing in mind if you have a powerloss no-one is going to have computers etc to access said servers The normal point is to be able to shutdown them safely without losing data, or to hold over a small power loss for a few minutes etc

 

Steve

[Steve21]

To give an example, our current cluster is using a Smart-UPS X 3000 (About £2k~)

 

Now with 2 Node cluster, storage, and core switch on it, it's currently showing available run time of 24min 39sec (Obviously power dependant on your equipment)

 

So if you're talking approx. £2k per 20mins, scale it to how long you're after basically

 

Steve

[Optimus_Primal]

This thing will keep the site going for i think it was something like a day. I will check with them. I just saw the bill for it and i have so many questions. I foresee a phone conversation tomorrow!

[Optimus_Primal]

Hahaha as much as i am a computer science teacher i am going to have to sit and try to find out how i would even get that info tomorrow.

[Steve21]

Frankly that just isn't normal for 99.9% of schools/business. If all you have is a 2 node cluster, someone obviously got a large backhander for that setup of the UPS!

 

It's not about how long it currently runs, but how long you need and why. If you're talking into days you'd be better off looking down the generator route

 

Steve

[Optimus_Primal]

Everything about the IT in the school was a backhander it was BFS money.

I am picking up the mess and trying to tidy it up.

[6Foot2]

Not sure what model they have now, but when I was working there, we had two rack mounted APC UPS units (The server room and the secondary backup server, with its own UPS, were physically separated)

 

Which model of APC UPS I couldn't say now.

[mrbios]

Whatever you go for, if it's backing critical hardware, make sure it's online rather than line-interactive. If you get line-interactive it's cheaper, but turn off green mode.

[DavR]

We just recently replaced a 10+ year old APC rackmount with the APC SMT2200RMI2UNC in our server room for under £1400. For that, we get our two servers, core switch and a monitor powered for about half an hour in the event of power loss. I think I worked out our maximum possible power load was about 1800W and went for a UPS that was 2200VA.

 

Due to power lost in covering AC-DC and then back again, the general rule of thumb is to assume the UPS is 80% efficient, so multiply the stated VA rating by 0.8, and that's how many watts it will support. In my case 2200VA x 0.8 = 1760W which was close enough (I was generous in my max load).

 

So start by working out what the total wattage of kit you need the UPS to support, and then think about how long you want it powered for in the event of an emergency. Unless it's running a critical system that can't be turned off, then most people just need 15-20mins for the servers to shut down.

[mavhc]

What will you want to do if the power goes out for the whole day? I assume continue to work for a while, phone all the parents and organise to shut down the school

 

Given laptops and PoE wifi and VoIP phones you could probably work on keeping that on for a hour or two. So 15 mins to realise the power isn't coming back, and then time to phone everyone and organise transport.

 

Calculate that amount of power, then you'll know what sized UPS you'll need

[ericdano]

We are APC. We had a few Emerson/Liebert units, but have been recently told that getting batteries for them is not going to be possible. And the batteries I have bought were almost as much as replacing the unit with an APC.

 

Our datacenter also has a 10 year old APC Symmetra lx system that works fine and I can still get parts and batteries for.

 

I'd only go APC at this point. They have a good track record of supporting their stuff.

[ericdano]

This is where you'd get a generator. Which is not really something most school sites can afford. Our main datacenter building has one, but the sites have MDFs and IDFs that have APC units in there that support the IP phones and speakers. The runtime is about 15 minutes, enough time to make calls and figure out what to do.

[mavhc]

There needs to be way more standardisation in batteries. Given they're all pretty much using the same 12V cells internally it's very silly that different APC models have different housings.

[3s-gtech]

They’re like projector lamps and toner cartridges, just a way to rinse customers. At least APC keep using the same battery type - our many generations of 3000VA models all use the same batteries.

[Optimus_Primal]

Well I was right in my suspicions. I just got this back from the company

 

"I have reviewed the output load data from the latest UPS Service Visits and agree that the load onsite is very low in comparison to the capacity of the UPS System.

Your current UPS System is designed to 40kVA N+1, consisting of 2x 40KVA UPS Modules. The site load, as per the last engineer report, is 5kW."

 

40kVA is the same output as a diesel generator. More than enough for my 2 node cluster!

[Guest Guest]

We've got 2x 3Kw APCs from when we had a 2 node cluster, they now both sit at about 20% utilisation with our core switch, 2 hyperv hosts, 2x routers and phone system. It keeps it going for about 1.5 hours

[mavhc]

Keep it to store solar power and then sell it back to the grid in the evening, it'll pay for itself

[pete]

We have an APC Symmetra (AP9619) in a 3 battery + 3 power module config (our load requires 2 power modules and at least 2 batteries, so we treat the third as redundancy). Runtime is ~25 minutes (or longer if we do some load shifting) because around here if the power's off for more than ~5-10 minutes it'll be off for hours.