XFS on ARM-based Linux on USR8700 NAS appliance w/ mdadm/RAID5

[Harry Mangalam]

Thanks for the quick response Eric!

On Monday 23 February 2009, Eric Sandeen wrote:
> Harry Mangalam wrote:
> > Here's an unusual (long) tale of woe.
> >
> > We had a USRobotics 8700 NAS appliance with 4 SATA disks in
> > RAID5:

<snip>

> However this wouldn't cause a superblock mis-read like this.  If
> you get it mounted, you *may* run into what looks like directory
> corruption on the PC, though, due to the alignment issue.
>
> Anyway, first, I'd look around for "XFSB" in the early few blocks
> of your raid and see if the raid might possibly have been rebuilt
> out of order.
>
> # dd if=/dev/md0 bs=4k count=32 | hexdump -C | grep XFSB
>
> or so...
>
> -Eric

No, I didn't find this - I did find some disk ID header stuff which 
confirms that the filesystem is XFS and some other info that might be 
useful, but no XFSB strings, even grepping 8MB into the device.

|<IPStorPartition|
| version="3.0" s|
|ize="595" owner=|
|"NACS-SW-DIST" c|
|hecksum="" signa|
|ture="IpStOrDyNa|
|MiCdIsK" dataSta|
|rtAtSectorNo="16|
|128" logvol="0" |
|category="Virtua|
|l Device"/>.<Phy|
|sicalDev guid="5|
|95e9fbb-1951-09c|
|3-a30c-000045d3a|
|a3b" Comment="" |
|WorldWideID="FAL|
|CON  LVMDISK-M09|
|N01  v1.0-0-0-00|
|"/>.............|
|................|

|<DynamicDiskSegm|
|ent guid="126de9|
|2f-98a1-3c06-01e|
|5-000045d3aa4d" |
|firstSector="161|
|28" lastSector="|
|22271" owner="NA|
|CS-SW-DIST" data|
|set="1171499597"|
| seqNo="0" isLas|
|tSegment="true" |
|sectorSize="512"|
| type="Umap" lun|
|Type="0" timesta|
|mp="1171499597" |
|umapTimestamp="0|
|" deviceName="NA|
|SDisk-00002" fil|
|eSystem="XFS"/>.|
|<DynamicDiskSegm|
|ent guid="126de9|
|2f-98a1-3c06-01e|
|5-000045d3aa4d" |
|firstSector="222|
|72" lastSector="|
|2928740095" owne|
|r="NACS-SW-DIST"|
| dataset="117149|
|9597" seqNo="1" |
|isLastSegment="t|
|rue" sectorSize=|
|"512" type="NAS"|
| lunType="0" tim|
|estamp="11714995|
|97" umapTimestam|
|p="0" deviceName|
|="NASDisk-00002"|
|/>..............|
|................|


-- 
Harry Mangalam - Research Computing, NACS, E2148, Engineering Gateway, 
UC Irvine 92697  949 824-0084(o), 949 285-4487(c)
---
Good judgment comes from experience; 
Experience comes from bad judgment. [F. Brooks.]