1 UPS for 2 boxes...?

[SilverJS]

So I now have two fully functioning FreeNAS boxes, main and backup. They're located physically close to one another. (I know, partly defeats purpose - but for now, it's what I've got.)

Still don't have a UPS, and will remedy that soon. But can one UPS "service" two FreeNAS boxes? I mean - I understand I could plug both boxes in it, but the USB cable could only go to one of the boxes. Is there a way I could have the other one shutdown too at the same time, when and if shutdown for the first is triggered...?

Cheers!

 

[marbus90]

The integrated NetworkUPStools supports a client/server model, even supports windows clients.

 

[joeschmuck]

If you will have another UPS soon, you might be better off just waiting for it vice trying to force something else. But as marbus90 said above, you could setup the FreeNAS machine with the UPS USB to send a message to the FreeNAS machine without the UPS USB to have it shut down over the Ethernet. I don't know how to do that but I'm certain someone does.

 

[depasseg]

Fully supported. http://doc.freenas.org/9.3/freenas_services.html#ups

The FN with the UPS is the master and the other is a slave. They will communicate over the network. When the USB one loses power, it will inform the slave. You can have multiple slaves, and since it uses NUT, these can be pretty much any device.

 

[SilverJS]

Awesome, thanks for replies. I had indeed looked at docs before posting question, but still not sure as to what in there (other than the reference to "Master/Slave" in the table) I could have used to gleam that what I wanted to do was possible. Glad it is in either case!

So - looking at my specs below, how much of a UPS do you guys reckon I'd need...? Something like 300 watts enough? I'd only want a shutdown initiation after a 10-second or so timer for both machines.

 

[depasseg]

Sorry, but I don't know that part. 300 seems very low though. Especially if you are running 2 machines off the same UPS temporarily. There are a bunch of UPS runtime calculators out there. Plug in running watts and desired uptime and it will give you a suggested VA rating.

 

[Tywin]

Sorry, but I don't know that part. 300 seems very low though. Especially if you are running 2 machines off the same UPS temporarily. There are a bunch of UPS runtime calculators out there. Plug in running watts and desired uptime and it will give you a suggested VA rating.

Note that the VA rating doesn't correlate directly with uptime, it tells you what maximum apparent power the UPS can support. It is the battery capacity that will determine your uptime.

 

[depasseg]

What is the measure of battery capacity?

 

[Tywin]

What is the measure of battery capacity?

Amp-hours (Ah) or watt-hours (Wh) typically. Bigger batteries often use kWh.

 

[marbus90]

APC has runtime for a given load charts for every single of their models. You'd still want a UPS which holds at least ~5-10 minutes.

 

[joeschmuck]

A 300 watt UPS is pretty small for a NAS but if you only use it to shut down your NAS after say a 10 second power loss, it will be fine. I am of course assuming you do not have any other devices (monitors, speakers, printers) plugged into the UPS Battery side. The real trick is to know if your UPS can handle both NAS's at the same time under full load and then you pull the power cord on the UPS.

Everyone has their own way of using an UPS, some want to power down immediately upon a power interruption and others like myself would rather wait until there is almost no power remaining in the UPS, ensuring short term brownouts or power losses does not turn off the NAS. I prefer to have an UPS which would power my NAS for 30 minutes minimal under normal power load.

 

[depasseg]

I guess that was my point. They don't list UPS's according to Wh or Ah. They list them according to power (VA) and then factor in various loads to calculate the runtime.

 

[Tywin]

I guess that was my point. They don't list UPS's according to Wh or Ah. They list them according to power (VA) and then factor in various loads to calculate the runtime.

Sure, they can market it however they want (note that the APC UPSs he is referencing also give you the efficiency with respect to loading, which is yet another factor that comes into play). My point was that VA alone still isn't going to give you the uptime.

 

[depasseg]

Agree

 

[rogerh]

The quoted uptime is best case, when the batteries are new. But the VA rating also has to be high enough to cope with maximum inrush current on startup. I would not try to use less than say 750VA for two modern computers.

 

[SilverJS]

Thanks for all the replies, gents. The power doesn't go out for long very often here - but, it does seem to flicker every once in a while. So, I'd only need both boxes to hold for like 10 seconds or so, then start shutdown. And no, nothing else at all plugged into it - just the two NAS boxes.

Heck - just today, the power flickered like four times this morning! But that's exceptional.

 

[rogerh]

You want to be sure that if the power goes out, even for half a second, while both machines are spinning up that the total current doesn't trip the current cut out on the UPS. And note that the power (i.e. in phase current times mains voltage) rating of the UPS is somewhere in the very small print but is possibly about two thirds of the VA rating.

 

[pschatz100]

You should have enough UPS capacity for the machines to run for a minute or so, then another 5 minutes or so to complete a graceful shutdown. Since no hardware specs have been mentioned, it would be impossible to guess what capacity would be needed. Also, be aware that many of the smallest UPS systems do not offer USB support to talk to the server.

While you can set up a master/slave UPS arrangement, I have just found it easier to buy one UPS per FreeNAS system. The smaller UPS units are not expensive, and you don't really need one with an LCD or fancy bells and whistles.

 

[jasonk]

If you are setting up a master slave model, remember your network switch/hub will also need to be on UPS, else the network command to shutdown the slave isn't going to make it out of the master.

 

[SilverJS]

Went out yesterday and got myself a CyberPower CP1000AVRLCD - it was one of the few available at my local shop that both was compatible, and was well-reviewed. Only 10$ more locally than at Newegg, which is very atypical. Anyway - I bought it in the evening but didn't set it up yet - thought I'd wait until morning.

Anyhow, it's hooked up now, and boy am I glad. Because - of course! - we had another major power loss last night. I'm guessing the power went off and on a couple of times, to boot, but I can't be sure. Either way, I was SO pissed at myself for not installing the UPS....but, now, it's up, and it's showing 2/5 bars for load. Setting up the USB now.

If you are setting up a master slave model, remember your network switch/hub will also need to be on UPS, else the network command to shutdown the slave isn't going to make it out of the master.

I had done that out of instinct already, because I figured the exact same. BUT - just to confirm...:

Both my FreeNAS boxes are in the basement. My router is upstairs. I have one CAT5E cable coming in to the basement, which is hooked up to a 10-port switch, and all the other peripherals - including both servers - are on that switch. The UPS is downstairs, next to the two servers, and the switch is indeed hooked up to the UPS, but what if the router isn't? Will the message still get through then?