Disks out of sync

Disks out of sync

[Mike Parsons]

Hi all

I have a 3 disk soft raid5 array. One disk has failed. Due to a
faulty removable drive tray the other disks are out of sync. The data on
the remaining disks should be identical.

Can someone please refresh my memory, on how to re-sync the disks. 

Thank You.

Mike Parsons 

Re: Disks out of sync

[Adam Luter]

Apparantly it should happen automatically when you put the drive back
in.  (And raidstop/start the drive).  If not, while the array is
started, run 'raidhotadd' on the drive.  It will treat the out of sync
drive as a new spare.. then once it's done syncing the spare it will
treat the spare as if it was the drive missing (that is, it will
upgrade it's status as a spare to a full fledge drive).

p.s. I'm not an expert, but I did just have to do this on mine (except
the auto part didn't work, so I had to use the hotadd part).

-Gryn (Adam Luter)

On Mon, Sep 30, 2002 at 02:56:49PM +0100, Mike Parsons wrote:
> Hi all
> 
> I have a 3 disk soft raid5 array. One disk has failed. Due to a
> faulty removable drive tray the other disks are out of sync. The data on
> the remaining disks should be identical.
> 
> Can someone please refresh my memory, on how to re-sync the disks. 
> 
> Thank You.
> 
> Mike Parsons 
> 
> -
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Re: Disks out of sync

[Mike Parsons]

On Mon, 30 Sep 2002, Adam Luter wrote:

> Apparantly it should happen automatically when you put the drive back
> in.  (And raidstop/start the drive).  If not, while the array is
> started, run 'raidhotadd' on the drive.  It will treat the out of sync
> drive as a new spare.. then once it's done syncing the spare it will
> treat the spare as if it was the drive missing (that is, it will
> upgrade it's status as a spare to a full fledge drive).
> 
> p.s. I'm not an expert, but I did just have to do this on mine (except
> the auto part didn't work, so I had to use the hotadd part).
> 
> -Gryn (Adam Luter)
> 

Thanks for the reply Adam, but the 2 good disks are not being recognised,
as the superblocks are out of sync. I have approx. 40 GB of data that I
would like to recover. 

I had this problem a while ago, and someone on the
list explained how to resync the suberblocks. Unfortunately the e-mail
with the information is on the raid array. Hopefully someone can refresh
my memory.

Cheers

Mike Parsons

Re: Disks out of sync

[Mads Peter Bach]

Mike Parsons wrote:
> Hi all
> 
> I have a 3 disk soft raid5 array. One disk has failed. Due to a
> faulty removable drive tray the other disks are out of sync. The data on
> the remaining disks should be identical.
> 
> Can someone please refresh my memory, on how to re-sync the disks. 

It's in the FHOWTO:

http://www.tldp.org/HOWTO/Software-RAID-HOWTO-6.html#ss6.1

Mark your failed disk as failed in /etc/raidtab and do a mkraid

-- 
Mads

Re: Disks out of sync

[Mike Parsons]

OOPS sorry people. I have been looking at an old printed copy of the
(F)HOWTO. I'll check current info before asking next time.

Cheers

Mike Parsons