2009/8/4 mcclnx mcc mcclnx@yahoo.com.tw:
we have CENTOS 4.X on DELL server and one one of virtual disk include 4 disk configure as REID5 (one more disk for hot spare). I saw /var/log/messages file have:
Aug 4 06:27:02 host1 Server Administrator: Storage Service EventID: 2094 Predictive Failure reported: Physical Disk 1:5 Controller 0, Connector 1 Aug 4 06:27:02 host1 Server Administrator: Storage Service EventID: 2051 Physical disk degraded: Physical Disk 1:5 Controller 0, Connector 1
I use DELL OPMN to check and found "disk 1:5" still "online", but "predicate failure".
I also use DELL OPMN to check virtual disk and it show "online", not "degrade".
my questions are:
is this disk really "degrade" or not?
how O.S. can predicate disk going to failure?
There are several possibilities, the most likely being that the drive's predict-fail bit flipped, or the # of sectors available for reallocation dropped below the manufacturer's recommended threshold. The following links have additional information on drive failures, and how to use SMART data to look at drive health:
http://www.usenix.org/events/fast07/tech/schroeder/schroeder_html/index.html
http://prefetch.net/articles/diskdrives.smart.html
Thanks, - Ryan -- http://prefetch.net