Read this http://www.dataclinic.co.uk/raid-server-faults.htm

You should never run chkdsk in /F or /F/R mode on a RAID array. Chkdsk is
not RAID aware, and will simply try to analyse and fix the NTFS tree as if
dealing with a normal disk. In doing so, it can write over information in a
degraded RAID array, that might have been recoverable at a lower level. You
can run it in read mode, but I would use the RAID controllers software. You
should be able access during machine boot up process. This should have
several options on checking for disk failure and recovery.

Chkdsk might be able to fix file system errors but it cannot do a surface
scan since it does not have access to any of the physical surfaces. I have
lost an array doing chkdsk on a raid array. That is why proper power
backup, data backup and recovery procedures are such a critical part of any
server setup.


Bryan


"Brian Cryer" <not.here@localhost> wrote in message
news:u7kpnZB7IHA.4468@TK2MSFTNGP02.phx.gbl...
> <rosgiof@hotmail.it> wrote in message
> news:c25a8ff9-7d7c-4e2c-bbcd-743afbddfe19@z72g2000hsb.googlegroups.com...
>> Hi all.
>>
>> I've googled a lot, but I've found out various and different opinions:
>>
>> Is it correct to use chkdsk /F and chkdsk /F /R on a RAID 1 system and
>> on a RAID 5 (with 3 HDs) system ?
>> All my systems are hardware RAIDs and the servers are domain
>> controller with w2k srv and w2k3 srv.
>
> I would have thought so, yes - because a RAID controller should present
> the RAID as a single disk to windows and windows shouldn't even need to be
> aware that its a RAID.
>
> chkdsk /f checks for logical corruptions, which could still occur whatever
> type of RAID you have if you ever shutdown in an ungraceful manner.
>
> chkdsk /r checks for bad sectors. This is probably pointless because even
> if one of the physical disks had a bad sector the raid controller (whether
> raid 1 or raid 5) should return the correct contents.
>
> So I would have thought chkdsk /f but not /r.
>
> Presumably if the RAID is failing (controller error or multiple disk
> errors) then chkdsk might report an error but chkdsk will not be able to
> fix the problem because the problem is with the underlying RAID. In this
> scenario chkdsk might even make things worse! So if you ever need to run
> chkdsk also check the state of the RAID controller.
> --
> Brian Cryer
> www.cryer.co.uk/brian
>
>
>