Servers with redundant power supplies

Jeff Zylstra · August 15, 2012, 03:58:20 PM

Quote from: Mark on August 15, 2012, 03:34:10 PM
I think that's old tech, Jeff. what kind of UPS are you using? My UPS tells me the load, the charge, and when to change the batteries. See pic.

EDIT: Also, my UPSs are under spec'd based on everything I said in previous post. In addition to that, they are only meant to keep the systems alive long enough to shut down gracefully. If we want an hour of battery life, we'd be looking at nearly $10,000 for a single UPS. The cheapest one I spec'd on APC.com was around $7,700 I think. We have a decent generator, so if the power is out long enough, I just fire that baby up, run some custom extension cords, and we're back in business. Of course, I plug each UPS into the generator to ensure clean power.

Oops. I was referring to the UPS units that I have on all of the workstations, not the server unit. The smaller ones don't have any LED lights, so I have to plug into those periodically. My big rackmount APC 1500 does have those lights, but invariably we have a power outage and someone's computer goes down or reboots. Then they're mad at me because they've lost work or were inconvenienced when no one else was. Once a year probably isn't enough, but it's what I can manage.

Mark · August 15, 2012, 03:59:22 PM

ahh, makes perfect sense! I wish we had those. I am jealous!

Jeff Zylstra · August 15, 2012, 04:41:35 PM

Quote from: Mark on August 15, 2012, 03:59:22 PM
ahh, makes perfect sense! I wish we had those. I am jealous!

All it takes is for a computer to reboot when someone is doing the most important proposal of their life, and you'll have them soon enough. I think the UPS units were like $50 apiece, or maybe less than that. But we also have we have a generator that demands that we have something to filter the power from the generator. Without that filter, the computers won't even run on generator power alone.

Mark · August 15, 2012, 04:47:44 PM

Yep, I know how that goes. Our power has gotten better in the past few years, but we use to lose it a lot. Our generator is not wired into the building. It is big enough to power the phones and data equipment and one or two workstations which is all we would need. If we ever have a prolonged power outage, we'll send people home with a CD or thumb drive that gives them all remote access. I can even fire up some SIP extensions if necessary.

I can't see them buying 32 UPSs though. Maybe a few critical ones, but then batteries are another expense. This comes up every two years or so around here and we just haven't done it yet.

Jeff Zylstra · August 15, 2012, 05:15:55 PM

Quote from: Mark on August 15, 2012, 04:47:44 PM
Yep, I know how that goes. Our power has gotten better in the past few years, but we use to lose it a lot. Our generator is not wired into the building. It is big enough to power the phones and data equipment and one or two workstations which is all we would need. If we ever have a prolonged power outage, we'll send people home with a CD or thumb drive that gives them all remote access. I can even fire up some SIP extensions if necessary.

I can't see them buying 32 UPSs though. Maybe a few critical ones, but then batteries are another expense. This comes up every two years or so around here and we just haven't done it yet.

I understand. We've had 2 multi-day power outages because of ice storms and 1 from a tornado, so getting a generator wasn't a choice. We HAVE to up and operational, even if no one else is. The funny part is that the power lines are down across our street half of the time, so the police close our road half of the time. But we can park on a side street and walk, so we do what we have to.

Jim Jensen · August 16, 2012, 10:23:54 AM

Since we have some people here with experience with generators, help a guy out a little - I've been tossing around the idea with a friend about buying one that we can have together as a disaster plan for each of our agencies. The chances of both of us being out of power is not terribly great. Ice storm would be the most likely reason and they usually spread their outages enough to be in our favor - we're about 3 miles apart on completely different main service lines. In a worst-case scenario, we'll forward one offices phone lines to the other and temporarily co-locate.

So - how big of a generator do we need? We would want to run a server, plus 2-3 workstations if we can, plus a phone main box that doesn't draw much energy. I've never known much about how much wattage I'd need or doing the wattage conversion for computers, etc.

Ian Blundell · August 16, 2012, 11:37:46 AM

Watts = Volts x Amps so a regular 110v 20amp circuit would be 2,200 watts. If you think that you could plug your servers, workstations, etc. into a single circuit without it tripping the breaker then that should give you an idea of the size of generator you would need.

Mark · August 16, 2012, 11:39:13 AM

And remember to ALWAYS plug the UPS into the generator. Do NOT plug your equipment directly into the generator.

Jeff Golas · August 16, 2012, 12:00:49 PM

Quote from: Ian Blundell on August 16, 2012, 11:37:46 AM
Watts = Volts x Amps so a regular 110v 20amp circuit would be 2,200 watts. If you think that you could plug your servers, workstations, etc. into a single circuit without it tripping the breaker then that should give you an idea of the size of generator you would need.

Should always up the need a little bit as most generators are rated for "peak" current - meaning 2200 watts would be running the thing at full tilt and having it probably run hot. If you used a 3000w generator it wouldn't be taxed 100% of the time.

Jim Jensen · August 16, 2012, 02:12:53 PM

Quote from: Ian Blundell on August 16, 2012, 11:37:46 AM
Watts = Volts x Amps so a regular 110v 20amp circuit would be 2,200 watts. If you think that you could plug your servers, workstations, etc. into a single circuit without it tripping the breaker then that should give you an idea of the size of generator you would need.

I've no idea. Short of plugging them all into as an experiment, I'm nowhere closer. Paging Dr. Hans -- I believe you've run some meters to measure such a number.

Hans Manhave · August 20, 2012, 05:10:37 PM

Quote from: Jim Jensen on August 16, 2012, 02:12:53 PM
Quote from: Ian Blundell on August 16, 2012, 11:37:46 AM
Watts = Volts x Amps so a regular 110v 20amp circuit would be 2,200 watts. If you think that you could plug your servers, workstations, etc. into a single circuit without it tripping the breaker then that should give you an idea of the size of generator you would need.

I've no idea. Short of plugging them all into as an experiment, I'm nowhere closer. Paging Dr. Hans -- I believe you've run some meters to measure such a number.

Assuming that I'm being referenced, I'll add what I know. Didn't see the message till now. Must submit forum enhancement (tapatalk or Simple Machines) to e-mail me when certain words (like my name) are being used.

I have a device to measure wattage use that plugs in between the wall socket and the device. Kill-A-Watt or something like that it is called. Inexpensive and fun to play with. You could measure between the UPS and the wall, then add them up plus some extra.

We have run this office on a several generators for several days during the ice storm of December 2000 (I think it was then). We laid a whole wire tree down the length of the office, with Romex, junction boxes etc. We used the UPS units to plug into that. There were not many problems. We used those generators that welders carry on their pickups or trailers. If you do use those, make sure you make it next to impossible to remove them without certain equipment because they are often stolen in this part of the country.

Running full size office printer/coper/scanner/fax machines may not be possible. They draw an enormous amount of power on startup. But in those emergencies, one may just bring one or more inkjet units from home.

Remember to provide power for the internet router, network switches and other such easily overlooked closet material. Also remember the phone system!

Jim Jensen · August 21, 2012, 09:27:57 AM

Not that Facebook is a medium to copy, but it would be interesting if we had the ability to 'tag' someone in a post and have it notify them.

So do you have a rough idea what size generator was able to run a certain number of computers?

Gene Foraker · August 21, 2012, 02:29:34 PM

I have the Kill-a-watt device Hans mentioned. It is fun to work with.

The best small generators are the Honda EU2000i. 2000 honest watts and they are small, light weight, easily stored and transported and whisper quiet. They are VERY popular with RVers and boaters. You can get the companion unit which hooks two together in parallel to double your power. They cost under $1000 each. They claim the power output is stable enough for computers.

Gene Foraker · August 21, 2012, 02:34:05 PM

Oh, to answer how much power you need, look at the printer. Laser printers take up gobs of power. You might be able to get away with 2000 watts to power a server, one workstation and a printer, but I think two of the Honda units I mention below would be better and you could throw in another workstation or two.

Ian Blundell · August 21, 2012, 04:32:02 PM

How long an extension cable can you use with these generators? They have to be outside when they are running and we are up on the 2nd floor with the computer room in the center of the building away from any windows.
We would also need to power internet/phone equipment in the basement. Wonder if we could just run those on a UPS since they probably don't take much power.