topic Re: Disk failure - "fsck: cannot initialize aggregate" in Operating System - HP-UX

Disk failure - "fsck: cannot initialize aggregate"

Chris Bensend — Tue, 08 Apr 2003 19:32:14 GMT

Hey folks,

We had a disk failure on an HP-UX 11.00 machine yesterday. The disk is an external 36G drive.

The disk contained several home directories that I'd really really like to recover (please don't ask about backups, I know, I know), but it seems to have failed in a way I haven't seen before.

Upon boot, the machine fails to mount the disk, complaining about "no such device". I attribute that to the fstab likely being out of date. Doing an ioscan reveals the following two disks:
10/0/15/1.5 target
10/0/15/1.5.0 disk SEAGATE ST336704LC
10/0/15/1.6 target
10/0/15/1.6.0 disk SEAGATE ST336704LC

Taking a look in /dev/dsk, I see devices for c3t5d0 and c3t6d0. c3t6d0 is vg00, so I assume the external drive is c3t5d0.

So, I attempt to fsck it manually:

[44] % fsck -y -F vxfs -o full /dev/rdsk/c3t5d0
invalid super-block
search for auxiliary super-block? (ynq)y
alternate super-block not found
vxfs fsck: cannot initialize aggregate
file system check failure, aborting ...

Not good. I'd appreciate any help any of you can provide - SAM considers it "unused", and nothing I've tried has worked so far.

Thanks a BUNCH!

Benny

Re: Disk failure - "fsck: cannot initialize aggregate"

Eugeny Brychkov — Tue, 08 Apr 2003 19:54:47 GMT

Benny,
as usual:
1. 'ioscan -fn' and check if disk is CLAIMED and DEVICE;
2. 'diskinfo -v' to see if disk reports correct block size, number of block, its capacity and vendor/serial number strings;
3. dd from the disk to /dev/null device using bs=4096k. This way you'll check surface for read operation.
If all these will be successful then you simply have data corrupt on the disk. Go to Vogon Intl. at http://www.vogon-international.com
Eugeny

Re: Disk failure - "fsck: cannot initialize aggregate"

Patrick Wallek — Tue, 08 Apr 2003 19:55:49 GMT

YOu really need to know what Volume Group and Logical Volume(s) were on that disk.

First do an 'ioscan -fnC disk' to see the disks and their device files.

Then do a 'strings /etc/lvmtab' to see which VG that disk belonged to. You could also try doing a 'pvdisplay /dev/dsk/c?t?d0' to see what VGs and LVs were on that disk.

Once you know what the VG name is, do a 'vgchange -a y vg??' to activate the VG. Then try doing a 'fsck -F vxfs -o full -y /dev/vg??/rlovl?'.

You can then try to mount the LV 'mount /dev/vg??/lvol? /mountpointname'.

Re: Disk failure - "fsck: cannot initialize aggregate"

Chris Bensend — Tue, 08 Apr 2003 20:08:56 GMT

Thanks for the quick replies...

The ioscan and diskinfo seemed to display good info - it is marked as CLAIMED in the ioscan, and the diskinfo reports the correct parameters.

This disk wasn't part of a volume group - it was simply newfs'ed and mounted, so the LVM stuff won't help.

Are there further steps I can take to try to recover the data (short of the data recovery service - the budget is VERY tight, although we'll have to if I can't do it)?

Thanks!

Benny

Re: Disk failure - "fsck: cannot initialize aggregate"

S.K. Chan — Tue, 08 Apr 2003 20:18:16 GMT

Is this disk (c3t5d0) a LVM disk or not ? If it is your fsck syntax should really be checking the logical volume instead of the physical disk. For example (assuming c3t5d0 is in vg01)..
# fsck -y -F vxfs -o full /dev/vg01/lvol1
If it's a whole disk configuration (not LVM) then the fsck syntax would be.
# fsck -y -F hfs /dev/rdsk/c3t5d0
What's in /etc/lvmtab ?
# strings /etc/lvmtab

Re: Disk failure - "fsck: cannot initialize aggregate"

John Dvorchak — Tue, 08 Apr 2003 20:36:26 GMT

I suppose that if you had another 36gb disk that you could newfs and mount that possibly you could dd the data from the failed disk to the new disk.

I am a little fuzzy here though. You said it "failed" and now it won't fsck the /dev/rdsk or mount it. You also said that /etc/fstab is "out of date"? I would suggest that you try to mount it the old fashioned way to see if there is anything you can do with the disk:

mount /dev/dsk/c3t5d0 /tmp_mnt

See what error, if any is generated. Notice I did not put a -F or any other switches, I am just curious what errors it generates.

No matter what happens with this test, I would suggest that you make your fstab file "Up to date".

Re: Disk failure - "fsck: cannot initialize aggregate"

Michael Steele_2 — Tue, 08 Apr 2003 23:17:49 GMT

You've got absolutely no LVM at all? So a vgcfgrestore won't help.

# vgfcgrestore -n /dev/rdsk/
# vgchange -a y /dev/vgname

What capcity was this 36gig disk at before this problem? Create another file system of equvivalent size and try a low level backup with dd. First, see what's there:

dd if=/dev/rdsk/c3t5d0 of=/tmp/file bs=2048 count=1000

Then, if happy:

dd if=/dev/rdsk/c3t5d0 of=/tmp/file bs=2048

Re: Disk failure - "fsck: cannot initialize aggregate"

Jon Finley — Wed, 09 Apr 2003 03:15:10 GMT

Are you sure that this disk was vxfs? The error you're getting is the same error as if you ran fsck on a disk that had hsf on it.

Jon

Re: Disk failure - "fsck: cannot initialize aggregate"

Jon Finley — Wed, 09 Apr 2003 03:16:34 GMT

Well.. I tried to type hfs. :-(

Jon

Re: Disk failure - "fsck: cannot initialize aggregate"

Ravi_8 — Wed, 09 Apr 2003 04:31:35 GMT