I have a CentOS-5.6 remote server in a house in Italy, where there are occasional thunder-storms. There was one yesterday, when the electricity went off 3 times, for a second or so on each occasion. My server, an HP MicroServer, came back (re-booted) on 2 of the 3 occasions, but not on the third. I assume that the problem arises because the machine does not close down properly. (Although it is also possible that a voltage surge might have been responsible - I have no surge protector on this supply.) It seems to me that it should be possible to have a simple, torch-battery operated, system which will keep the machine alive long enough to make a graceful exit. A full-blown UPS would be excessive, I think, as I only want the machine to re-boot when the current comes back on. I know there is a Remote Management (iLO) card for this machine, which might be useful for this. Unfortunately, I've already used the PCIe slot for a second ethernet card. Any advice or suggestions gratefully received. -- Timothy Murphy e-mail: gayleard /at/ eircom.net tel: +353-86-2336090, +353-1-2842366 s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland
On Fri, Jul 1, 2011 at 7:05 PM, Timothy Murphy <gayleard at eircom.net> wrote:> It seems to me that it should be possible > to have a simple, torch-battery operated, system > which will keep the machine alive long enough > to make a graceful exit. > A full-blown UPS would be excessive, I think, > as I only want the machine to re-boot > when the current comes back on.I believe a personal UPS would be quite cheap. Much cheaper than losing data. The UPS can tell the OS to shutdown on power loss.
On Fri, 1 Jul 2011, Timothy Murphy wrote:> I have a CentOS-5.6 remote server in a house in Italy, > where there are occasional thunder-storms. > > There was one yesterday, when the electricity > went off 3 times, for a second or so on each occasion.<snip> Just buy a really basic UPS. I don't know what the prices are like where you are, but a crappy 500VA UPS can be had for about 25 uk pounds. I've only ever monitored APC UPSs which can be monitored easily from linux, so check for linux compatibility before buying something obscure. jh
On Fri, Jul 1, 2011 at 1:05 PM, Timothy Murphy <gayleard at eircom.net> wrote:> I have a CentOS-5.6 remote server in a house in Italy, > where there are occasional thunder-storms. > > There was one yesterday, when the electricity > went off 3 times, for a second or so on each occasion. > > My server, an HP MicroServer, > came back (re-booted) on 2 of the 3 occasions, > but not on the third. > > I assume that the problem arises because the machine > does not close down properly. > (Although it is also possible that a voltage surge > might have been responsible - > I have no surge protector on this supply.) > > It seems to me that it should be possible > to have a simple, torch-battery operated, system > which will keep the machine alive long enough > to make a graceful exit. > A full-blown UPS would be excessive, I think, > as I only want the machine to re-boot > when the current comes back on. > > I know there is a Remote Management (iLO) card > for this machine, which might be useful for this. > Unfortunately, I've already used the PCIe slot > for a second ethernet card. > > Any advice or suggestions gratefully received. > > -- > Timothy Murphy > e-mail: gayleard /at/ eircom.net > tel: +353-86-2336090, +353-1-2842366 > s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland > > _______________________________________________ >A UPS would be your simplest option here since the UPS can send a signal to the OS to shutdown properly. Using a "torch battery" (I presume this is a large torch?) you'll still have the same issue as you have now - when the battery runs flat (i.e. power outage is longer than 10 minutes or so) Linux will still crash uncleanly. -- Kind Regards Rudi Ahlers SoftDux Website: http://www.SoftDux.com Technical Blog: http://Blog.SoftDux.com Office: 087 805 9573 Cell: 082 554 7532
On Fri, Jul 1, 2011 at 7:05 AM, Timothy Murphy <gayleard at eircom.net> wrote:> I have a CentOS-5.6 remote server in a house in Italy, > where there are occasional thunder-storms. > > There was one yesterday, when the electricity > went off 3 times, for a second or so on each occasion. > > My server, an HP MicroServer, > came back (re-booted) on 2 of the 3 occasions, > but not on the third. > > I assume that the problem arises because the machine > does not close down properly. > (Although it is also possible that a voltage surge > might have been responsible - > I have no surge protector on this supply.) >I've seen this happen before. The machine looses power long enough for the system to hang as the proper voltage is not maintained, but not long enough for it to turn off. A cheap UPS is what you need. Just something to smooth out the momentary power faults so the machine can shutdown or restart. A APC Back-UPs would be perfect and shouldn't break the bank. You don't need an expensive sinewave output like the APC Smart-UPS for what you are trying to accomplish. Ryan
On Friday 01 July 2011 12:05, Timothy Murphy wrote:> > Any advice or suggestions gratefully received.If you are thinking of the UPS route a caveat: I have several HP servers and most of them will not work on cheap UPS's as they do not produce the pure sine wave modern HP machines require but rather a crude stepped voltage. Colin.
On 7/1/11, Timothy Murphy <gayleard at eircom.net> wrote:> It seems to me that it should be possible > to have a simple, torch-battery operated, system > which will keep the machine alive long enough > to make a graceful exit. > A full-blown UPS would be excessive, I think, > as I only want the machine to re-boot > when the current comes back on.Like others have suggested, a cheap UPS is the way to go. The problem with your idea is that you'll need a DC to AC inverter that can handle the output current required by your server and something to hold the batteries (you'll need more than one because attempting to draw a huge current from a normal battery will either kill it or at the very least cause it to have a shorter than expected capacity) and everything together, it's probably going to cost more in both money and time to have this thing.
You should invest in a Spider KVM or similar, they hang off the back and don't use any rack space. They can also be POE, so they wont use a plug. That'll provide you out of band management and remote reboots and what not. On Fri, Jul 1, 2011 at 7:05 AM, Timothy Murphy <gayleard at eircom.net> wrote:> I have a CentOS-5.6 remote server in a house in Italy, > where there are occasional thunder-storms. > > There was one yesterday, when the electricity > went off 3 times, for a second or so on each occasion. > > My server, an HP MicroServer, > came back (re-booted) on 2 of the 3 occasions, > but not on the third. > > I assume that the problem arises because the machine > does not close down properly. > (Although it is also possible that a voltage surge > might have been responsible - > I have no surge protector on this supply.) > > It seems to me that it should be possible > to have a simple, torch-battery operated, system > which will keep the machine alive long enough > to make a graceful exit. > A full-blown UPS would be excessive, I think, > as I only want the machine to re-boot > when the current comes back on. > > I know there is a Remote Management (iLO) card > for this machine, which might be useful for this. > Unfortunately, I've already used the PCIe slot > for a second ethernet card. > > Any advice or suggestions gratefully received. > > -- > Timothy Murphy > e-mail: gayleard /at/ eircom.net > tel: +353-86-2336090, +353-1-2842366 > s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos >-- Steven Crothers steven.crothers at gmail.com -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.centos.org/pipermail/centos/attachments/20110703/65c95f42/attachment-0002.html>
Steven Crothers wrote:> You should invest in a Spider KVM or similar, they hang off the back and > don't use any rack space. They can also be POE, so they wont use a plug. > That'll provide you out of band management and remote reboots and what > not.How exactly would that work? -- Timothy Murphy e-mail: gayleard /at/ eircom.net tel: +353-86-2336090, +353-1-2842366 s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland
They have cheaper smaller UPS's that should be able to help you. On Fri, Jul 1, 2011 at 7:05 AM, Timothy Murphy <gayleard at eircom.net> wrote:> I have a CentOS-5.6 remote server in a house in Italy, > where there are occasional thunder-storms. > > There was one yesterday, when the electricity > went off 3 times, for a second or so on each occasion. > > My server, an HP MicroServer, > came back (re-booted) on 2 of the 3 occasions, > but not on the third. > > I assume that the problem arises because the machine > does not close down properly. > (Although it is also possible that a voltage surge > might have been responsible - > I have no surge protector on this supply.) > > It seems to me that it should be possible > to have a simple, torch-battery operated, system > which will keep the machine alive long enough > to make a graceful exit. > A full-blown UPS would be excessive, I think, > as I only want the machine to re-boot > when the current comes back on. > > I know there is a Remote Management (iLO) card > for this machine, which might be useful for this. > Unfortunately, I've already used the PCIe slot > for a second ethernet card. > > Any advice or suggestions gratefully received. > > -- > Timothy Murphy > e-mail: gayleard /at/ eircom.net > tel: +353-86-2336090, +353-1-2842366 > s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland > > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos >-- http://www.theboxery.com -- -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.centos.org/pipermail/centos/attachments/20110704/1d307cb8/attachment-0002.html>
On 07/01/11 4:05 AM, Timothy Murphy wrote:> It seems to me that it should be possible > to have a simple, torch-battery operatedassuming 'torch' in this context means what us yank's call a flashlight, and that a 'torch battery' is a C or D cell, lets see how much juice we could get out of a reasonable setup.. According to HP's 'quick specs', the Microserver has a 150W supply, that nominally draws 0.63 A (from 115VAC) or 0.35 A rom 220VAC, about 75 watts. According to wikipedia, an alkaline D cell is typically rated at 1.2 amp hours at 1.5 volts. Most inexpensive AC inverters run on 12V (automobile power), so we'd need 8 of them to get 1.2AH at 12V or about 14 watt*hours... My calculations seem to suggest you'd get maybe 9 minutes total from those 8 batteries with an 80% efficient AC inverter at 75 watts. And then of course, you'd be throwing those 8 D cells away and replacing them with new ones. NiCAD or NiMH rechargeable batteries aren't particularly suitable for this application, you'd need 10 of them as they are 1.2V, and they don't do well as standby power since they self discharge when idle for long periods. UPS's almost always use lead-acid batteries as they are far more suitable for standby power applications. A UPS is little more than a rechargeable battery, an A/C inverter circuit, a battery charger, and a controller for all that which also signals your computer when the power is failing. -- john r pierce N 37, W 122 santa cruz ca mid-left coast
James Matthews wrote:> They have cheaper smaller UPS's that should be able to help you.What UPS's are you suggesting? (I didn't really follow your remark.) -- Timothy Murphy e-mail: gayleard /at/ eircom.net tel: +353-86-2336090, +353-1-2842366 s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland
On Saturday, July 02, 2011 09:00:54 AM Jason Pyeron wrote:> You will either need many different batteries for the different voltages (1.2, > 3.3, 5, 12, -12, -5) or a DC ATX power supply (not cheap and not very powerful > until the 48V input variety)A company called PowerStream produces DC input ATX supplies for 12V, 24V, and 48V input, all with up to 500W of power. The 12V input page is at http://www.powerstream.com/DC-PC-12V.htm We have a number of their -48V input supplies in use. No, the 500W version in 12V input is not cheap.
On Wednesday, July 06, 2011 05:23:32 AM Ljubomir Ljubojevic wrote:> Lamar Owen wrote: > > We have a number of their -48V input supplies in use. No, the 500W version in 12V input is not cheap. > > There are smaller and cheaper 12V solutions Like the picoPSU's: > http://www.mini-box.com/picoPSU-160-XTSure; we have a couple of small units like that for some solar-powered things we're doing here; however, the max I've seen for those plug-in type small ATX/ITX power supplies has been in the ~200W range (the specific one you linked to is only 160W), and my reply was specifically directed at the idea that lower than 48 VDC input was limited in power handling...... PowerStream has a 500W 12VDC input unit, which is quite a bit more power than I've seen in the mini-ITX plugin supply categories.
On Wednesday, July 06, 2011 12:24:12 PM John R Pierce wrote:> 500 watts at 12VDC is 41 amps. that requires some hefty wiring, and if > you have to run it any distances, either the wire is ridiculously heavy > (and expensive) or you suffer from voltage drop under load.While not CentOS-specific, this *is* in my area of expertise. We have 540Ah of -48VDC driven by a pair of Lorain Flotrol 200A rectifiers for our telco equipment (including the Cisco 12008 and OSR7609 routers). Our solar sites are mostly 24VDC with, again, 540Ah minimum at each site, with a few 12VDC systems with 75 to 300Ah at each site. I've run enough 4/0 and larger flex cables, that's for sure..... for 41 amps, up to 25 feet or so, relatively small 8AWG is sufficient. That's smaller gauge than the 6AWG and 4AWG I ran for the 12008 and 7609, respectively, for -48VDC power. (I say relatively small; the largest conductor size we have here is 6kA rated busbar, so even 2AWG or 2/0 AWG is relatively small......:-) ) I've seen much larger, specifically in the Brookhaven 5ESS in Atlanta. I remember seeing one branch circuit idling at ~2.5kA. Hmmm, speaking of 5ESS, I wonder what the chance of a CentOS for a 3B15 or 3B20 would be? :-) (No, Russ, before you ask: I don't still have the 3B15's that used to be here.....) For a reference on DC power design, useful if you need to support CentOS servers with DC supplies in a telco environment, please see "DC Power System Design for Telecommunications" by Whitham D. Reeve for the 'canonical' reference work. Everything you need, including current limit and overcurrent protection, low-voltage cutouts, distribution design, voltage drop and wire sizing calculations, and ampacity tables for DC (NEC includes AC ampacity tables, but not DC). And I have a few CentOS boxes running on DC power. And, of course, having powertop running on CentOS, and having some low-power modes, helps tremendously.
On Wednesday, July 06, 2011 05:23:36 PM John R Pierce wrote:> On 07/06/11 2:07 PM, Ljubomir Ljubojevic wrote: > > This part of the thread is about DC input ATX power supplies,> ah. thats not what is commonly referred to as 'the ATX connector', so I > was confused.If you looked at the power supply Ljubomir previously linked to in the thread (not the PowerStream unit, but the picoPSU one), you'd see that that particular DC input power supply is built on the ATX connector itself and has no separate mechanical case. And gets 160W output power; which is excellent, for an 'on-connector' power supply. The whole supply is not much larger than the ATX connector itself; seriously, go look at this little gem. At that point you could put a 12V power supply and a sealed lead-acid battery inside the PC case where the PSU normally goes..... you'd just have to make sure you add a schottky diode in series, since this picoPSU requires regulated 12VDC input and has overvoltage protection set around 13.0 to 13.5 volts (lead acid float voltage 13.8 typical). A 13.5 volt dry cell string and a 13.5 volt regulated power supply with a pair of 1.5V drop power diodes preventing the dry cells from charging would also work, and that sort of arrangement would indeed be a 'torch' battery (common usage here is 'flashlight' rather than 'torch').... and that would fit the needs of the OP. The PowerStream unit can work with unregulated 9-18 volts input, and would be more suited to raw battery input. Again, a diode isolator (similar to an automotive accessory battery isolator diode set) would be required if non-rechargeable batteries were to be used as the backup. Speaking of, I actually have some old Mirapoint rackmounts, running CentOS of course, that have built-in UPS's and redundant PSU's; haven't been able to figure out whose UPS so that I could use them with apcupsd.
On Thursday, July 07, 2011 12:05:30 PM Ljubomir Ljubojevic wrote:> Well, it is not viable to run PC of the batteries (for long), but > hooking it up directly to the battery of the UPS (so UPS charges that > battery) is what I intend to do (There is nowhere to purchase them in my > country yet :-( ).Looking at the way the picoPSU implements the +12V output, it should be possible to use the lm_sensors package in CentOS, or the motherboard manufacturer's utility (like SuperoDoctor for Supermicro motherboards) and get an alarm and an orderly shutdown based on the +12V line's voltage. Could be an interesting application.... But until you can get one.....