Need help to recover system

[Henry Chua]

HI Guys need some urgent help,

I have recently experienced acrash in my system. In order to recover my system, I have cloned the harddisks using a cloning machine. however when putting the cloned disks back into the system, I faced a problem...
one of the LV is spanned between 2 PVs and I cant seem to mount it..

the lvdisplay produce this:
PV Name /dev/dsk/c0t6d0
LV Name LE of LV PE for LV
/dev/vg09/stand 12 12
/dev/vg09/root 150 150
/dev/vg09/swap 32 32
/dev/vg09/dump 32 32
/dev/vg09/opt 110 110
/dev/vg09/usr 100 100
/dev/vg09/tmp 25 25
/dev/vg09/var 33 33
/dev/vg09/lvcustomer 17 17

PV Name /dev/dsk/c0t5d0
/dev/vg09/lvcustomer 511 511

as u can see lvcustomer is span between 2 PVs .. Must I do anything to make it work.. I have try using fsck but it prompted me an error of a missing or corrupted "superblock".. try fsck -b using a block from "sbtab".. didnt work either.. can anyone help me?

MANY Thanks to all for your answers!!!

[Brian Markus]

I'm just throwing out stuff, in an attempt to help. When I've had a corrupted superblock in the past I've used fsck with these options with success.

/sbin/fs/vxfs/fsck -F vxfs -o full -y /dev/vg09/rlvcustomer

I don't see how cloning the crashed system disks will help? Do you have an ignite backup? Or some other backup you can recover from?

I've never seen vg09 as the main vg, that's a bit weird. Not that that makes much of a difference. It would hover clash if your minor numbers are the same as some other vg on the system, however, if this is a clone of the disk it should be the way it was prior to crashing. You might want to try doing a test read (dd) to the disks to make sure everything is phisically ok.

Good luck

-Brian.

[Henry Chua]

Hi,

Had tried "fsck -F vxfs -o full -y /dev/vg09/rlvcustomer" didnt quite work..
System prompted that missing or corrupted superblock or wrong magic no. Have tried "fsck -b 16 /dev/vg09/rlvcustomer, didnt work. thus tried the bigger block number in "/etc/sbtab" but system prompted "
ROOT INNODE CORRUPTED
FIX? yes
ALLOCATE BLOCK FOR ROOT DIR? yes
c/0: Bad Magic Number
Could not allocate block
unable to fix root innode.

Anyone know how I can resolve this?...

THank you all for your advises!

[Sridhar Bhaskarla]

Hi,

If this is a vxfs filesystem, then you cannot use '-b
Are both disks available to the system?. Do

ioscan -fnC disk

and make sure no "NO_HW" is showing up against these disks.

Also, do a

dd if=/dev/rdsk/c0t5d0 of=/dev/null bs=1024k

Shouldn't produce any I/O errors. Also look at /var/adm/syslog/syslog.log for any errors related to "PV".

If both the above are good, then

vgchange -a y vg09
vgdisplay -v vg09 shouldn't produce any "disk doesn't match' type of errors.

Post the observations of all the above and some will be able to assist you.

-Sri

[Henry Chua]

Thanks Sri, for your advises,

Can I acertain the first system to be HFS if "fsadm -F hfs /dev/vg09/rlvcustomer" produce
"file system : /dev/vg09/rlvcustomer
magic number : 95014
feature bits : 1
file system supports: nolargefiles,longfilenames"
.."ioscan -fnCdisk" produce no perculiarity..
no error observed with "dd if=/dev/rdsk/c0t5d0 of=/dev/null bs=1024k"..syslog.log doesnt show any thing wrong with the PVs . "vgchange -a y /dev/vg09" then "vgdisplay -v /dev/vg09" appears ok... the lvcustomer portion is as such "
LV Name /dev/vg09/lvcustomer
LV Status available/syncd
LV Size (Mbytes) 2112
Current LE 528
Allocated PE 528
Used PV 2
"

Is anything wrong with the above observation.. please let me know if you want me to send more info in details...

Thank you all for your support

[Sridhar Bhaskarla]

Hi,

You can very well do 'fstyp -v /dev/vg09/lvcustomer' to find out the type of the filesystem. If this is a HFS filesystem, you will find the alternate superblocks in the file /var/adm/sbtab.


-Sri

[Henry Chua]

Hi Sri,

Thank you for your reply, I have checked and comfirmed that it is HFS. I have tried using the spare blocks in sbtab; I tried using 16 and others but it doesnt seem to help.

I have this ridiculous idea, can I delete the lvcustomer and reinstate it again.. can this be done?.. I have backed up the lvcustomer data.. so I should not lose any data.. but how should I create a LV exactly as the one I used to have.. since this LV span between 2 PVs...

Many thanks to u and others for your kind help!

Henry

[Sridhar Bhaskarla]

Hi,

You didn't do a "newfs" anytime on this logical volume. Did you?.

One another way to check that there are no disk errors would be to do

dd if=/dev/vg09/rlvcustomer of=/dev/null bs=1024k

You shouldn't see any errors. If that is the case, then the filesystem is corrupted..

You can recreate if you are confident on the backup. All you ahve to do is to run "newfs -F hfs" again. Or I would suggest that you create another logical volume if you have space in the VG and then restore the backup on it. Once the recovery is good, then you can remove lvcustomer logical volume.

newfs -F hfs /dev/vg09/rlvcustomer.

Mount it and restore the data.

-Sri