Re: failed raid re-create changed dev size

["Andris Berzins" <pkix@inbox.lv>]

Quoting "Robin Hill" <robin@robinhill.me.uk>:
>>> I don't know off the top of my head how to change the mdadm data offset
>>> unfortunately.
>>> 
> There's no way in the current mdadm releases to do so. Neil does have a
> version in git which will allow specifying the data offsets on a
> disk-by-disk basis (as it is possible to have multiple offsets within an
> array). If all the disks in your array were using an offset of 2048
> though, then you'll just need to downgrade mdadm to 3.2.3 (or slightly
> earlier) - from what I can find it was changed to 262144 for 3.2.4 (it
> was 272 pre version 3.0, so don't go any further back than that).

Downgraded to mdadm version 3.2.3 and re-created array successfully!

> 
> You will likely have lost some data though, as the new superblocks will
> have overwritten part of the data, so make sure you run a fsck
> afterwards (start with fsck -n though, to make sure the overall array
> looks okay first).

Is it possible that no data was damaged? It is LUKS partition, i mapped it and run "fsck -n" on underlying ext3 partition, 
but fsck returned immediately with status "clean".


> Good luck (and please make sure you try just forcing an assemble next
> time),

I will try to contact these blog authors, who suggested to re-create failed array instead of forcing an assemble, to make a 
notice on their blogs.


> Robin
> --
> ___
> ( ' }     |       Robin Hill        <robin@robinhill.me.uk> |
> / / )      | Little Jim says ....                            |
> // !!       |      "He fallen in de water !!"                 |