topic Re: Recover data on bootdisk in Operating System - HP-UX

Recover data on bootdisk

reis — Wed, 15 Feb 2006 03:33:35 GMT

Hi,
after reboot I get an error:
panic: all VFS_MOUNTROOTs failed, Need Divers ?
There are data on the harddisk, which i have to back up. How can i mount or even repair this bootdisk on another system without loosing data on it ?

Kind regards
Walter Reis

Re: Recover data on bootdisk

dhananjay_1 — Wed, 15 Feb 2006 03:45:49 GMT

Hello ,

Have u made any chages to the logical volumes/Filesystem or you are getting this error mesg after new installation.

Give some more inputs .

Regds
DJ

Re: Recover data on bootdisk

reis — Wed, 15 Feb 2006 03:50:19 GMT

Hi, there was a system crash and then I got this error. I hope, that the harddisk isnÂ´t defect.

Re: Recover data on bootdisk

Devender Khatana — Wed, 15 Feb 2006 04:16:41 GMT

Hi,

This is not the case of disk failure and the data must be intact, you can very well recover this on some other system supporting this disk.

I experienced this error on a R-380. The disk was intact and I recovered all the data and even after reloading the OS the same disk worked fine for years ahead.

You can import this VG on some other system. If there were more than two disks in this vg00 then I recommend to attach both disks to the system where you wish to recover.

#insf (To create new disk device file if the disks are hot-swappable and you plugged in online.)

Note down the device files for one or two new disks.

#mkdir /dev/oldvg00
#mknod group c 64 0x??0000

(Where ?? is the unique no. on the new system. Confirm by "ll /dev/*/group" and use next available number.)

#vgimport /dev/oldvg00 disk_device_file/files

#ll /dev/oldvg00

You should see all old LVOLs here and can mount them using

#mkdir oldroot
#mount -F vxfs /dev/oldvg00/lvol3 /oldroot

Similarly you can mount other file systems, but note that you will not be able to mount lvol2 bsing swap and lvol1 will be a HFS file system. Any other swap LVOLs existing previously also can not be mounted.

HTH,
Devender

Re: Recover data on bootdisk

Abhijit P. — Wed, 15 Feb 2006 04:20:33 GMT

Hi...

1.boot the system with the Core-OS Install CD .
2.Go to the recovery shell
3.Run a fsck on root volume lvol3

this will clean the superblock flag and allow you to boot the system.

Regards,
Abhijit

Re: Recover data on bootdisk

Mridul Shrivastava — Wed, 15 Feb 2006 04:32:42 GMT

Have u checked why system crashed??
Have u installed any s/w, why did u go for restart.
U dump the PIM output and post it if possible it will help us in arriving at root cause "Why system crashed?"
As far as data is concerned it safe.

Re: Recover data on bootdisk

Kent Ostby — Wed, 15 Feb 2006 04:42:42 GMT

Walter --

The error listed above is most likely not fatal. It is usually caused when lvm data structures become damaged and it is usually fixable.

Here are the steps:

1) boot the system in -lm mode
(i.e. hpux -lm)

2) this should bring you to a prompt where none of the volume groups are active. So activate your root volume group:

vgchange -a y /dev/vg00

3) Once the VG activates, check the lvlnboot information:

lvlnboot -v /dev/vg00

4) Check to see if you have a line that says "No boot lvol defined" or something similar.

A "good" layout (with mirrored disk) looks something like this:

Boot Definitions for Volume Group /dev/vg00:
Physical Volumes belonging in Root Volume Group:
/dev/dsk/c0t6d0 (10/0.6.0) -- Boot Disk <--- Primary boot disk
/dev/dsk/c0t5d0 (10/0.5.0) -- Boot Disk <--- Mirror boot disk

Boot: lvol1 on: /dev/dsk/c0t6d0
Boot: lvol1 on: /dev/dsk/c0t5d0 <---------- Mirror boot disk
Root: lvol3 on: /dev/dsk/c0t6d0
Root: lvol3 on: /dev/dsk/c0t5d0 <---------- Mirror boot disk
Swap: lvol2 on: /dev/dsk/c0t6d0
Swap: lvol2 on: /dev/dsk/c0t5d0 <---------- Mirror boot disk
Dump: lvol2 on: /dev/dsk/c0t6d0, 0

5) If you do then type the following:

lvlnboot -b /dev/vg00/lvol1
lvlnboot -R /dev/vg00

6) Now do lvlnboot -v /dev/vg00 to see the data again.

7) reboot

If this doesn't fix the panic, but you were able to do the initial reboot into -lm then replace step 5 with a complete rebuild of the BDRA:

"lvrmboot -r /dev/vg00" Removes the info from the BDRA
"lvlnboot -b /dev/vg00/lvol1" Writes the boot info to the BDRA
"lvlnboot -r /dev/vg00/lvol3" Writes the root info to the BDRA
"lvlnboot -s /dev/vg00/lvol2" Writes the swap info to the BDRA
"lvlnboot -d /dev/vg00/lvol2" Writes the dump info to the BDRA
"lvlnboot -R /dev/vg00" Updates the BDRA

Best regards,

Oz

Re: Recover data on bootdisk

reis — Wed, 15 Feb 2006 07:09:24 GMT

I tried to start hpux -lm.
I get the message
vxfs fsck filesystem had I/O errors on meta data
log replay in progress
pass0
pass1

Then the system tries to make a dump
Then it reboots and "the same procedure" again
IÂ´ll try next to boot from CD like Abhijit told.