Alexander Georgiev spake the following on 7/27/2007 5:32 AM: > Hi people, > > I am building a cheap remote rsync backup server using a software raid > 5 array of 4 500GB disks. What I have available on the market is: > > 1. HITACHI GST Deskstar T7K500 500GB 7200rpm 16MB cache Serial ATA II-300 > 2. SEAGATE Barracuda 7200.10 with NCQ 500GB 7200rpm 16MB cache Serial ATA II-300 > 3. Western Digital 500GB SATAII RAID EDITION Caviar SE16 7200rpm 8.9ms > 16MB cache > > I am tempted to use the Western Digital Raid Edition as it has 5 > years of warranty. However I found out that the "Raid Edition" means > that the disk supports TLER - time limited error recovery: > > http://www.excelmeridiandata.com/products/wd_raid_edition_drive.shtml > > A more profound description can be found here > http://www.wdc.com/en/library/sata/2579-001098.pdf. > > In summary, the error recovery time of the hard disk is reduced to 8 > second. If the hard disk cannot perform the recovery it will report an > error to the RAID controller and delegate the recovery to the > controller. > > As I intend to use linux software raid on Centos 5, I will not have a > RAID controller to deal with this delegated error, but two cheap I/O > SATA controllers. > > Has anybody used 'raid edition' disks with software raid? > Does anybody know how linux software raid interacts/supports these TLER disks. > > Best regards > Alex I have used raid aware and non-raid aware disks for both hardware and software raid. You really want the raid edition drives, as they will send a fail up the channel much faster than a non-raid drive. The non-raid drives will retry over and over, and you stand a chance of data loss while they decide what to do. Software raid will just fail the drive and switch to degraded mode. -- MailScanner is like deodorant... You hope everybody uses it, and you notice quickly if they don't!!!!