From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Freemyer Subject: Re: RAID halting Date: Mon, 6 Apr 2009 18:16:50 -0400 Message-ID: <87f94c370904061516t51b74f26g9d2b02c09f27283f@mail.gmail.com> References: <87f94c370904051300x531acb1fqb55319536333c01f@mail.gmail.com> <20090405220311.YMPW19140.cdptpa-omta03.mail.rr.com@Leslie> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20090405220311.YMPW19140.cdptpa-omta03.mail.rr.com@Leslie> Sender: linux-raid-owner@vger.kernel.org To: lrhorer@satx.rr.com Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids >> Lot of reported problems turn out to be power supplies not designed = to >> carry a Sata load. =A0Apparently sata drives are very demanding and = many >> "good" power supplies don't cut the mustard. > > Well, the server itself only has a single PATA drive as its boot driv= e, and > the only peripheral card is the SATA controller. =A0It's a new chassi= s (6 > months) with a 550 Watt supply, so it's unlikely to be the culprit, e= ven > though the CPU is 125 Watts. =A0The RAID chassis is a 12 slot system = with a > 400 Watt supply and 11 drives. =A0I suppose I could try changing the = RAID > supply to a 600 or 700 watt model, but really 400W should be enough f= or 11 > drives and 3 port multipliers. =A0According to the spec sheets, the m= ost power > hungry drives in the mix (Hitachi E7K1000) require an absolute maximu= m of 26 > watts. =A0If all the drives were the same, that would be 286 watts. > Especially given the Western Digital drives and the one Seagate (not = part of > the array) drives are specified to have somewhat lower power consumpt= ion, > 400W should be fine. It may or may not be as simple as you describe. A lot of modern PSUs have multiple rails. Each rail is independent and provides some number of watts. So if your CPU / graphic rail(s) are getting 300 watts out of your 550, then that only leave 250. And that can be split among 2 or 3 rails as well. It definitely gets complicated. Or you may have a simple design where all the 5v lines are tied together, same for +12v,-12v. OTOH, if your having issues with power you should be seeing sata transmission errors reported in the kernel log. I don't recall your saying, but I assume you've been watching that and nothing is showing up during these events? Greg --=20 Greg Freemyer Head of EDD Tape Extraction and Processing team Litigation Triage Solutions Specialist http://www.linkedin.com/in/gregfreemyer =46irst 99 Days Litigation White Paper - http://www.norcrossgroup.com/forms/whitepapers/99%20Days%20whitepaper.p= df The Norcross Group The Intersection of Evidence & Technology http://www.norcrossgroup.com -- To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html