Friday, March 30, 2012

Raid5 and Suspect DB

I have a DB on a Raid 5 of 4 disks. One of the disks failed, freezed the
screen and everything else,
I was obliged to reboot
After reboot, My DB was in suspectmode, First question, if I am not
mistaken, as far as it is raid 5, the DB must not be in suspect mode
Ok, I used the last good full backup, DB came back on line. 2 hours or more
the same thing happened.
I wonder what is the efficiency of RAID 5
Perhaps the database was exactly in the middle of IOs and the Raid did not
cover it...Was the Raid array continuously available?
Asingle disk failure on Raid 5 should not have affected anything.
Wayne Snyder, MCDBA, SQL Server MVP
Mariner, Charlotte, NC
www.mariner-usa.com
(Please respond only to the newsgroups.)
I support the Professional Association of SQL Server (PASS) and it's
community of SQL Server professionals.
www.sqlpass.org
"SalamElias" <eliassal@.online.nospam> wrote in message
news:C7D83256-BDCA-41D4-A45C-214CF0F47202@.microsoft.com...
> I have a DB on a Raid 5 of 4 disks. One of the disks failed, freezed the
> screen and everything else,
> I was obliged to reboot
> After reboot, My DB was in suspectmode, First question, if I am not
> mistaken, as far as it is raid 5, the DB must not be in suspect mode
> Ok, I used the last good full backup, DB came back on line. 2 hours or
more
> the same thing happened.
> I wonder what is the efficiency of RAID 5
|||Thanks for your response, when you say DB was in the middle of IOs, I
understand when reading Books on line or any other docs regarding DBs
recovery plan should be able to handle these events (rol back or roll forward
in case of disk failure. AmI mistaken?
I confirm it wa a one disk failure. Also one more strange thing happened, I
changed the faulty disk, deleted the database, tried to recreate it, It was
not possible (got error messages). I changed the physical datafile place (on
the raid 0 log disk), DB was created. Any ideas or thoughts.
Thanks again
"Wayne Snyder" wrote:

> Perhaps the database was exactly in the middle of IOs and the Raid did not
> cover it...Was the Raid array continuously available?
> Asingle disk failure on Raid 5 should not have affected anything.
> --
> Wayne Snyder, MCDBA, SQL Server MVP
> Mariner, Charlotte, NC
> www.mariner-usa.com
> (Please respond only to the newsgroups.)
> I support the Professional Association of SQL Server (PASS) and it's
> community of SQL Server professionals.
> www.sqlpass.org
> "SalamElias" <eliassal@.online.nospam> wrote in message
> news:C7D83256-BDCA-41D4-A45C-214CF0F47202@.microsoft.com...
> more
>
>

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