topic Re: About vgcfgrestore in Operating System - HP-UX

About vgcfgrestore

Eric Antunes — Mon, 16 Mar 2009 08:19:46 GMT

Hi,

Will "vgcfgrestore -n /dev/EVA00 /dev/rdsk/c6t0d1" restore /dev/EVA00/disc4 file that was damaged by mistake?

Thanks,

Eric

Re: About vgcfgrestore

Robert-Jan Goossens_1 — Mon, 16 Mar 2009 08:31:31 GMT

Hi Eric,

No it will not restore the device file, this will restore the LVM (VolumeGroup) information to the disk.

If the device file has been altered/removed you can use the mknod or the insf -e "hardwarpath" to recreate the device file.

Regards,
Robert-Jan

Re: About vgcfgrestore

Jozef_Novak — Mon, 16 Mar 2009 08:32:12 GMT

Hello Eric,

vgcfgrestore restores the LVM Physical volume header onto the target disk. This enables recovery of a lost LVM configuration but not of any data.

J.

Re: About vgcfgrestore

Fabio Ettore — Mon, 16 Mar 2009 08:45:50 GMT

Hi Eric,

vgcfgrestore restores LVM configuration from file, no data which has to be restored by a backup. Hope you have that.

Best regards,
Fabio

Re: About vgcfgrestore

Eric Antunes — Mon, 16 Mar 2009 10:22:24 GMT

The data was not really important: just archivelogs.

What I really want is to restore the logical volume "/disc4" availability, if it is possible.

I already executed the "insf -e -H hw-path" but fsck returns the following:

fsck -F vxfs /dev/rdsk/c4t0d3
vxfs fsck: not a valid vxfs file system
invalid super-block
vxfs fsck: cannot initialize aggregate
file system check failure, aborting ...

Re: About vgcfgrestore

Eric Antunes — Mon, 16 Mar 2009 10:29:30 GMT

Maybe a full check "fsck -F vxfs -ofull,nolog /dev/rdsk/c4t0d3" will work?

Re: About vgcfgrestore

Jozef_Novak — Mon, 16 Mar 2009 10:31:44 GMT

Hello Eric,

the physical volume /dev/rdsk/c4t0d3 does not contain a filesystem directly, since it is configured in LVM. Get the list of logical volumes from dev/EVA00 by running:

# vgdisplay -v dev/EVA00

Then select the logical volume that you want to repair and run:

# fsck -F vxfs /dev/EVA00/disc4 ,for example

Hope this helps,
J.

Re: About vgcfgrestore

Ganesan R — Mon, 16 Mar 2009 10:38:52 GMT

Hi Eric,

If the LVM header has been accidently overwritten or became corrupted on the disk you can recover it from the backup file using vgcfgrestore.

# vgcfgrestore -n vgXY /dev/rdsk/c1t6d0

But keep in mind this before restore the headers.

vgcfgrestore cannot be performed on devices attached to activated volume groups. Prior to restoring a backup configuration to a disk, detach the PV from the volume group using the pvchange(1M) command, or deactivate the volume group using the vgchange(1M) command.

So either you need to detach the pv from the VG or deactivate the VG before use vgcfgrestore on that disk.

Re: About vgcfgrestore

Robert-Jan Goossens_1 — Mon, 16 Mar 2009 10:54:02 GMT

Hi Eric,

--
"fsck -F vxfs -ofull,nolog /dev/rdsk/c4t0d3"
--

Only if you have created a filesystem on the complete disk.

# fsck -F vxfs -o full,nolog /dev/vgxx/lvoly

Regards,
Robert-Jan

Re: About vgcfgrestore

Eric Antunes — Mon, 16 Mar 2009 11:08:32 GMT

Hi,

Full fsck did not work:

fsck -F vxfs -y -ofull /dev/EVA00/disc4
vxfs fsck: OLT extent 0 has bad magic
read of primary OLT failed
vxfs fsck: OLT extent 1 has bad magic
read of OLT copy failed
vxfs fsck: no valid OLT, cannot continue
file system check failure, aborting ...

Re: About vgcfgrestore

Eric Antunes — Mon, 16 Mar 2009 11:15:49 GMT

Yes, c4t0d3 had only /disc4.

The same result with -ofull,nolog:

fsck -F vxfs -n -ofull,nolog /dev/EVA00/disc4
vxfs fsck: OLT extent 0 has bad magic
read of primary OLT failed
vxfs fsck: OLT extent 1 has bad magic
read of OLT copy failed
vxfs fsck: no valid OLT, cannot continue

The use of nolog option is only relevant for clean (empty?) filesystems, right?

Re: About vgcfgrestore

Ganesan R — Mon, 16 Mar 2009 11:23:48 GMT

Hi Eric,

Few questions.

If the disk failed or LVM headers corrupted first you need to restore the LVM headers into the disk. Have you restored?

This restoration just update LVM headers not file system structures. You have two options here.

1. If all the data on the problematic disk was mirrored, you do not have to do anything; LVM automatically synchronizes the data on the disk with the other mirror copies of the data.

2.If the disk contained any unmirrored logical volumes (or mirrored logical volumes that did not have a current copy on the system), restore the data from backup, mount the file systems

If you are in option two, follow these steps.

# -> if necessary
# vgcfgrestore â n vg01 /dev/rdsk/c2t2d0
# vgchange â a y vg01
# newfs [options] /dev/vg01/rlvol1
# mount /dev/vg01/lvol1 /dump
#

fsck is not going to work unless you have created the filesystem onto the disk.

Re: About vgcfgrestore

Eric Antunes — Mon, 16 Mar 2009 12:04:13 GMT

Ganesan:

I will try this tonight with the volume group inactivated (the manual says that, preferably the volume group should be made unavailable before run this command):

#vgchange -a n /dev/EVA00
#vgcfgrestore -n /dev/EVA00 /dev/rdsk/c4t0d3 (this is the right raw device path name)
#vgchange -a y /dev/EVA00
#newfs ...

Thank you,

Eric Antunes

Re: About vgcfgrestore

Avinash20 — Mon, 16 Mar 2009 12:39:35 GMT

"The data was not really important: just archivelogs. "

If the disk is Ok then I would advice to recreate the FS. You need to restore the data again !!

# newfs -F vxfs /dev/

Re: About vgcfgrestore

Eric Antunes — Mon, 16 Mar 2009 14:48:14 GMT

Hi,

Ganesan' solution worked:

#vgchange -a n /dev/EVA00
#vgcfgrestore -n /dev/EVA00 /dev/rdsk/c4t0d3 (this is the right raw device path name)
#vgchange -a y /dev/EVA00
#newfs -F vxfs -o largefiles /dev/EVA00/rdisc4

Thank you,

Eric Antunes