RAIDframe corruption

[manu%netbsd.org@localhost (Emmanuel Dreyfus)]

Hello

I recently experience a weird RAIDframe corruption: this is a RAID 1 with two
disks, wd0 and wd1, and one day, the bootstrap on wd0 broke. Swapping the disks
made it boot again, but then Xen complainef that the dom0 NetBSD kernel was not
in ELF format. I reinstalled a new kernel and the system booted again.

Obviously I had some bits corrupted on wd0, but my problem is that now the
system boots again, I have no way to assert wether this system is sane or not:
neither fsck nor raidctl did find anything wrong with the filesystems and the
RAID set. the kernel does not report any I/O problem with the disks, the SMART
status are ok.

If I compare the 2048 first blocks of the disk, I can find a 32 bit word
difference at offset 0x1b8 in MBR, but I am not sure wether it is relevant (- is
the disks that boot, + is the disk with broken bootstrap):
 0190  0d 99 b6 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
 01a0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
-01b0  00 00 00 00 00 00 00 00  9f ba 9f ba e1 b5 80 20  |............... |
+01b0  00 00 00 00 00 00 00 00  00 00 00 00 e1 b5 80 20  |............... |
 01c0  21 00 a9 50 ff ff 00 08  00 00 b0 65 70 74 00 00  |!..P.......ept..|
 01d0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|

Anyone has advice on how to cope with this? It seems I have to reinstall MBR,
but since I had two idenpendant corruptions, I fear more widespread damage. 

-- 
Emmanuel Dreyfus
http://hcpnet.free.fr/pubz
manu%netbsd.org@localhost