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Best option for UPS on a budget for a Dell poweredge 1950
We have a Dell PowerEdge 1950 that was donated through a grant to us (non-profit) a few years back. We need a UPS to power it but are on a very limited budget. We are not worried about long runtime so much as just making sure it can shut down gracefully. It's a fileserver and DC, no exchange or SQL. The issue is it has dual power supplies, each one being about 670W according to Google.
Question is, does the server pull full power from each PSU during normal operation? We realilze ideally each PSU would have it's own UPS, but that may not be plausible unless absolutely necessary.
We are trying to find a good price on a name brand UPS that will meet its requirements, but really trying to stay at or under $ 200.
Thanks
Question is, does the server pull full power from each PSU during normal operation? We realilze ideally each PSU would have it's own UPS, but that may not be plausible unless absolutely necessary.
We are trying to find a good price on a name brand UPS that will meet its requirements, but really trying to stay at or under $ 200.
Thanks
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ASKER
Thanks. Tacotec, just to clarify, using your solution, in the event for whatever reason the power supply that was plugged into the UPS failed and the power flickered or went out, we would end up with an ungraceful restart or shutdown of the server, correct?
Granted it's not likely to happen as hopefully the failed power supply would be noticed, but still.
Granted it's not likely to happen as hopefully the failed power supply would be noticed, but still.
ASKER
Oh and yes, only 2 HDDs, simple Raid1.
The 1950 will pull 670W MAX. with with one PS running or with 2 splitting the load (redundancy)
yes - if the power-supply that is connected to the UPS failes DURING an power-outage, then the server is down.
if the power-supply failes without an power-outage, the second power-supply would take over the full load
You could also connect BOTH power-supplies to the same UPS (as charlestasse said, the 670W is the maximum of BOTH - so one power-supply could handle the full load) -> in this configuration one power-supply could fail also during power-outage, BUT if the UPS is damaged, the server is down...
personally I think that the risk of an UPS failure is higher than an power-supply outage just in the moment of an power-outage... (but both scenarios should allmost never hapen)
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ASKER
Thx. If the conclusion is we want a 1000va and that will handle one of the power supplies, we should be able to find that.
Check out Dell's 1000w Rack and Tower systems
dellups.com
dellups.com
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ASKER
Thanks! That Amazon deal should work great.
Quick question - with this APC 1500VA do we still only want to run one power supply into the UPS? If so, should we simply connect the other PSU to the surge protected only outlets on the UPS?
Thanks
Quick question - with this APC 1500VA do we still only want to run one power supply into the UPS? If so, should we simply connect the other PSU to the surge protected only outlets on the UPS?
Thanks
Plug in both PSU...no harm in that. If you're nervous about UPS hardware failure, then plug the other PSU into the wall on a SEPARATE circuit. In the future, you can get another UPS for the second PSU if you feel the need.
The redundant PSU is to avoid hardware failure of a single PSU.
A second power circuit will avoid accidental tripping or switching, which takes out both PSUs at the same time.
A second UPS on a separate circuit gives the most redundancy...if the power goes out completely, and you have a single UPS failure, the second UPS will take over. And yes...it has happened.
If it were me, I'd plug in one PSU to the UPS and the other PSU to an outlet on a separate circuit. But that's only because I know where all my circuits are going...little chance of someone messing up the wiring or getting to the breaker panel. If in doubt, put both PSUs into the UPS.
The redundant PSU is to avoid hardware failure of a single PSU.
A second power circuit will avoid accidental tripping or switching, which takes out both PSUs at the same time.
A second UPS on a separate circuit gives the most redundancy...if the power goes out completely, and you have a single UPS failure, the second UPS will take over. And yes...it has happened.
If it were me, I'd plug in one PSU to the UPS and the other PSU to an outlet on a separate circuit. But that's only because I know where all my circuits are going...little chance of someone messing up the wiring or getting to the breaker panel. If in doubt, put both PSUs into the UPS.
Yikes....don't forget to connect the cable and install the automatic shutdown software!
ASKER
Thanks. Probably wouldn't be easy to get to a second circuit where the server cage is situated here. Would be nice though.
If we connect both PSU's into the UPS, should one go through surge only or do you believe the UPS can handle the load on both?
Thx
If we connect both PSU's into the UPS, should one go through surge only or do you believe the UPS can handle the load on both?
Thx
Load is almost the same, whether you have one PSU plugged in or both. It's the total load of all components + "overhead" of 1st PSU + "overhead" of 2nd PSU. The overhead is the nominal wattage required to keep the PSU active, power the fan on idle speed, and power the LED status lights. That should be insignificant..
The greatest load is at power up, which is when all drives are spinning, and all fans run at full speed for about 10 seconds. That load (by specification) can't be higher than ~600W, since that is the limit of the PSU.
Hope that helps. Short answer: no problem.
The greatest load is at power up, which is when all drives are spinning, and all fans run at full speed for about 10 seconds. That load (by specification) can't be higher than ~600W, since that is the limit of the PSU.
Hope that helps. Short answer: no problem.
ASKER
Thanks. So even though both power supplies are rated for 675W, they will never both pull 675W so its okay to connect them both to the 1500VA/875W UPS?
If both PSU's are getting good power (either through the AC Utility power or off the battery) will the server pull all the power for the components from one PSU or divide the load? IE: if it takes 400W for the server to run normally with it's normal components, will it pull the 400W from one or 200W from each PSU?
On a sidenote: will connect the data cable as you stated, but do you know off-hand if the APC PowerChute software will work with this APC (Back-UPS Pro) and Win Server 2003? Last time we checked with APC they said the Back UPS (non-pro) software was designed for non-server OS'ses but we could use native Windows power management.
If both PSU's are getting good power (either through the AC Utility power or off the battery) will the server pull all the power for the components from one PSU or divide the load? IE: if it takes 400W for the server to run normally with it's normal components, will it pull the 400W from one or 200W from each PSU?
On a sidenote: will connect the data cable as you stated, but do you know off-hand if the APC PowerChute software will work with this APC (Back-UPS Pro) and Win Server 2003? Last time we checked with APC they said the Back UPS (non-pro) software was designed for non-server OS'ses but we could use native Windows power management.
Both PSUs will not run at full load at the same time. They are redundant supplies (N+1). Whether it's switched full load onto one PSU or shared between the two PSUs is up to the hardware configuration.
With 3 PSUs, N+1 redundancy means that the total load can be handled by 2 PSUs. And so on.
The unit I linked to is a "Pro" model. There is also a connection for an extra battery pack to increase your runtime. BR24BPG is the matching color.
IIRC, Windows power management should work fine. The specs list PowerChute "personal edition" is included for free. I think they are charging for servers now.
With 3 PSUs, N+1 redundancy means that the total load can be handled by 2 PSUs. And so on.
The unit I linked to is a "Pro" model. There is also a connection for an extra battery pack to increase your runtime. BR24BPG is the matching color.
IIRC, Windows power management should work fine. The specs list PowerChute "personal edition" is included for free. I think they are charging for servers now.
ASKER
Thanks. so at no point can both PSU pull 675W each? Where would you find out the max each would pull?
ASKER
Thx all, Aleghart if you don't mind still clarifying the last question that would be great. Didn't want to leave the original question open though.
If the power supply says "redundant (N+1)", then the system is designed to operate while one PSU is fully removed. So, take the max rating of the remaining PSUs, add a small percentage for the overhead of the "spare" PSU, and you have your theoretical max load. So, for 675W, your system should never pull over 700W.
I think without drives, those servers pull between 350-300W. That leaves you 300+ watts for hard drives. At ~10W or so per drive, you shouldn't be anywhere near the max of the PSU.
I think without drives, those servers pull between 350-300W. That leaves you 300+ watts for hard drives. At ~10W or so per drive, you shouldn't be anywhere near the max of the PSU.
ASKER
Ah, gotcha. That makes sense. So anotherwords, both drives can be connected to the battery side of the UPS because really even at full load the PSU's can't pull more than the max that one PSU would be able to pull (system at full capacity) + the minor overheard for the other PSU.
Correct.
ASKER
Thank you!
http://www.cpuid.com/softwares/hwmonitor.html