Re: Problems after reshaping of Raid5 array

[Michele Bonera <mbonera@gmail.com>]

Il giorno mar, 30/11/2010 alle 08.45 +1100, Neil Brown ha scritto:

> > Yesterday evening I added another WD, this time an EARS
> > (512 byte sectors): I created a partition on it, respecting the

Just to be precise: 4K byte sector (my mistake).

> Yes.
> I think you can fix it by simply failing and removing sdc
> Then md/raid5 will recover that data using the parity block, and that should
> be correct.
> It appears that the partition you created on the new device started at a
> multiple of 64K.  When this happen, the superblock at the end of the
> partition also looks valid when seen at the end of the whole device.
> Somehow mdadm got confused and choose the whole device (sdc) instead of the
> partition (sdc1).

I did it and it worked! Thanks a lot Neil!!!

> I am surprised at this because since mdadm-2.5.1, mdadm will refuse to
> assemble an array if it sees two devices that appear to have the same
> superblock.  Could you possibly be using something that old??

The distribution is Ubuntu Server 10.04, 
kernel 2.6.32-26-generic-pae, mdadm 2.6.7.1

Again many thanks Neil, you saved me! :)

Cheers,
--
Michele Bonera
linux user group brescia