How to enable volume group

[csreenivas]

We have rebooted the server.But we didn't see the vg02 after reboot? I have tried with vgchange but it is showing the below message.
Can anyone of you help me in this?

vgchange: Warning: Couldn't attach to the volume group physical volume "/dev/dsk/c2t4d0":
The path of the physical volume refers to a device that does not
exist, or is not configured into the kernel.

[DCE · Accepted solution]

You may of lost a disk during the reboot

Does dev/dsk/c2t4d0 show up as a claimed device with an ioscan -fnC disk?

Also, do a
strings /wtc/lvmtab
to see if c2t4d0 is actually assigned to vg02

[Steven E. Protter]

Shalom,

Depends on whether the vg is part of shared storage or serviceguard.

basic:
vgchange -a y vg02

Should activate the volume group.

Assuming it does not ever need to be activated on another system, you can auto activate in /etc/lvmrc

SEP

[csreenivas]

The disk c2t4d0 is not showing in ioscan.
It shows below info with strings /etc/lvmtab.

strings /etc/lvmtab
/dev/vg02
/dev/dsk/c0t3d0
/dev/dsk/c2t4d0
/dev/dsk/c4t5d0

Can you please help us in solving this issue.

[Geoff Wild]

If c2t4d0 doesn't show - then either your devs were renumbered or the disk has died.

If it has died, you should see a NO_HW in the output of an ioscan -funC disk

If that's the case, then you need to replace the disk and do a vgcfgrestore, then restore your data.

If the hardware is fine, you could try exporting/importing the vg:

vgexport -s -v -m /tmp/vg02.map /dev/vg02

mkdir /dev/vg02
mknod /dev/vg02/group c 64 0x020000

vgimport -s -v -m /tmp/vg02.map /dev/vg02

Rgds...Geoff

[DCE]

It sounds like you may of lost a disk. Hopefully the VG is mirrored, although if the vg will not come on line,it sounds like it is not.

Check your syslog for error messages.

If the disk is bad, you will have to get it replaced, and restore the data from your last good backup

[csreenivas]

When I try to export the vgo2 it is showing the below message.

#vgexport -s -v -m /tmp/vg02.map /dev/vg02
Beginning the export process on Volume Group "/dev/vg02".
Volume group "/dev/vg02" is still active.
vgexport: Couldn't export volume group "/dev/vg02"

[Robert Salter]

Did you do a diskinfo on the disk?
diskinfo /dev/rdsk/c2t4d0
Or a pvdisplay?
pvdisplay /dev/dsk/c2t4d0
Or as Geoff said did you get any NO_HWs in the ioscan?
If you can see the disk from any of the above and there isn't a NO_WH, then you may have lost the header info on the disk. You can recover it with a vgcfgrestore.

If you're going to do the vgexport and want to deactivate the volume group do a
vgchange -a n /dev/vg02

Think beer,
robert