From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stan Hoeppner Subject: Re: Green drives and RAID arrays with partity Date: Sun, 25 Sep 2011 06:43:36 -0500 Message-ID: <4E7F13E8.4080606@hardwarefreak.com> References: <4E7F0A31.4070001@yazzy.org> Reply-To: stan@hardwarefreak.com Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <4E7F0A31.4070001@yazzy.org> Sender: linux-raid-owner@vger.kernel.org To: lists@yazzy.org Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids On 9/25/2011 6:02 AM, Marcin M. Jessa wrote: > Hi guys. > > I was wondering if it's safe to use so called green drives in RAID 5 = or > RAID 6 with md? > Drive such as Seagate Barracuda=AE Green 2TB ST2000DL003 or Western > Digital Caviar=AE Green=99 2TB WD20EARX have TLER off and reading mis= c > forums I understand that it would be a good idea to buy drives with t= hat > option available. > On the other hand some people claim that Linux/Solaris/BSD based > software RAID may be able to work just fine with these drives. That won't make a lick of difference if you attach them to a crappy=20 HBA/RAID card or mobo down chip, and/or with a buggy driver, or plug=20 them into a crappy backplane. Note the recent discussion of the=20 SuperMicro/Marvell HBA, mvsas driver problems. When you have a problem such as yours, and you ask for help on this, or= =20 any other Linux kernel list, it's a really good idea to post all of the= =20 relevant information up front. Why? Because most often when drives=20 drop out of arrays it is not because a disk failed or the disk has bugg= y=20 firmware. It's most often because of problems elsewhere in the storage= =20 stack, either hardware or software. Crappy HBAs and/or drivers, loose or dislodged cable connectors, and=20 crappy active/passive backplanes are the primary movers when it comes t= o=20 good drives dropping out of arrays. That said, assuming you have a good SAS/SATA ASIC/driver combo and=20 stable backplane, etc, I'd say buy the WD RE4 or Seagate Constellation=20 ES as they have 5 year warranties, TLER, all the good stuff for RAID=20 use. Which is why they are sold as "enterprise" drives and cost more=20 than consumer cheapos like the various Green "drives". Both the RE4 2T= B=20 and Constellation ES 2TB are $200 each at Newegg. Unless you actually=20 *need* that much total space, I'd go with the 1TB models, paying ~half=20 the cost of the 2TB drives. The 1TB Constellation ES is $110. So with= =20 5 drives you'll save almost $500 on drives, with 4TB usable space with=20 RAID5. Again, I implore you to investigate all other portions of your storage=20 stack before blowing money on drives, which may not be the cause of you= r=20 problem. --=20 Stan -- 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