Recovering a GEOM RAID0 array

[Ivan Voras]

Juan Miscaro wrote:

> This is the end of dmesg (the drives in question are ad1 and ad3):

> GEOM_STRIPE: Device st0 created (id=3091204740).
> GEOM_STRIPE: Disk ad1 attached to st0.
> GEOM_STRIPE: Disk ad1 removed from st0.
> GEOM_STRIPE: Device st0 destroyed.
> GEOM_STRIPE: Device st0 created (id=3091204740).
> GEOM_STRIPE: Disk ad1 attached to st0.

Firstly, as you can see ad3 is never added. This can mean several
things, of which the most probable is that its metadata has been
destroyed. The messages after the second message is probably due to you
opening the drives manually, bypassing gstripe, probably with the
following commands.

> # bsdlabel ad1
> 
> # /dev/ad1:
> 8 partitions:
> #        size   offset    fstype   [fsize bsize bps/cpg]
>   a: 1250280640       16    4.2BSD     2048 16384 28552
>   c: 1250280656        0    unused        0     0         # "raw"
> part, don't edit
> partition a: partition extends past end of unit
> partition c: partition extends past end of unit
> bsdlabel: partition c doesn't cover the whole unit!
> bsdlabel: An incorrect partition c may cause problems for standard
> system utilities
> 
> # bsdlabel ad3
> 
> # /dev/ad3:
> 8 partitions:
> #        size   offset    fstype   [fsize bsize bps/cpg]
>   a: 625142432       16    4.2BSD     2048 16384 28552
>   c: 625142448        0    unused        0     0         # "raw" part,
> don't edit
> 
> These drives should appear to be identical.

This is the wrong way to inspect your drives. If you did anything to the
drives individually (i.e. bypassing gstripe) it's very likely you
corrupted some data. I don't know if this is obvious to you so I'm
saying it just in case. Inspect your drives with "diskinfo -v" to get
information such as its size.

What does "gstripe list" say? What does "sysctl -b kern.geom.confxml" say?

If "gstripe list" doesn't mention ad3, you need to establish what
happened to metadata on ad3. Try extracting the last sector from ad3 by
hand (using dd) into a file and inspect it (send output of "hd filename").

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 252 bytes
Desc: OpenPGP digital signature
Url : http://lists.freebsd.org/pipermail/freebsd-questions/attachments/20090331/2cb9ee17/signature.pgp