Re: Unable to fsck 4.5TB FFSv2 fs

[Stephen Borrill <netbsd%precedence.co.uk@localhost>]

On Thu, 25 Sep 2008, Juergen Hannken-Illjes wrote:
[snip]
> Are you sure your device is >4TB clean?
> Is there some magic using partition d (whole disk)?

Further testing:

It appears that there is indeed a problem on the larger of the two 
arrays. With the first array:

ld0 at aac0 unit 0: RAID 1 (Mirror)
ld0: 76188 MB, 9712 cyl, 255 head, 63 sec, 512 bytes/sect x 156033024 sectors

if I try to dd if=/dev/ld0d of=/dev/null skip=156033024, I get I/O errors 
as you would expect:

ld0d: error reading fsbn 156053504 of 156053504-156053507 (ld0 bn 156053504; cn 
9713 tn 224 sn 47)
ld0: I/O error: I/O error

If I try to do the same on the second, larger array:
ld1 at aac0 unit 1: RAID 5
ld1: 4656 GB, 607897 cyl, 255 head, 63 sec, 512 bytes/sect x 9765867520 sectors

i.e. I run:
dd if=/dev/ld1d of=/dev/null skip=9765867520

it just keeps running, so perhaps some 32-bit offset somewhere is 
overflowing and looping around.

--
Stephen