vgdisplay errors

[Joe Robinson_2]

In the past I had an external fast-wide SCSI drive hooked up for COOP/quick restore purposes. I've since moved on to a different hardware schema, and the volume group that was assigned to that disk removed. However, when I do a vgdisplay, I get the following error:

No such file or directory vgdisplay: Cannot display volume group ?/dev/vg31?.

How can I remove this 'ghost' image of the non-existant volume group?

Thanks in advance again,

Joe Robinson

[Sachin Patel]

I think vgcfgbackup will work

Sachin

[James R. Ferguson]

Hi Joe:

# vgexport /dev/vg31

Regards!

...JRF...

[Deshpande Prashant]

Hi
Export it out.
#vgexport /dev/vg31

Thanks
Prashant.

[Sanjay_6]

Hi Joe,

IF the volume group is active on your system, first disable it,

vgchange -a n /dev/vg_name

then to remove it completely from your system

vgexport /dev/vg_name

If there are any references of this vg in /etc/fstab, delete the same.

That should be all. Hope this helps.

thanks

[Joe Robinson_2]

Thanks to everyone who has responded...it's appreciated. I'd thought of the vgexport earlier, however, the device files are no longer in /dev, so the system can't recognize the export command.

none of the commands I'm looking at in the SA commands book seem to be able to recognize the commands. Looking further, I'd thought of recreating the vg on another disk, however I don't have any unused disks that I can create the vg on. Suggestions?

[Thierry Poels_1]

Hi,
if everything(!) is removed of that VG, you can rename /etc/lvmtab and execute 'vgscan -a'.

good luck,
Thierry.

[Santosh Nair_1]

Joe,

How did you remove the VG from the system originally? It sounds like you just removed the /dev/VGNAME files(?).

Do you see the VG if you do a strings on /etc/lvmtab?
If so, then recreate the VG:

mkdir /dev/VGNAME
mknod /dev/VGNAME/group c 64 0x0nn0000
vgcreate /dev/VGNAME

then if you want to get rid of the VG,
do a:

vgexport VGNAME

If the VG is not listed in /etc/lvmtab, then try doing a vgscan to try to rebuild the VG. Hope this helps.

-Santosh

[Joseph C. Denman]

The reason for the error is the device is still in the lvmtab. Export will not work because the device is gone. You will need to recreate your lvmtab. This is what I would do:

vgdisplay -v > /tmp/vgdis.before
mv /etc/lvmtab /etc/lvmtab.bak
vgscan
vgdisplay -v > /tmp/vgdis.after

vgscan will rebuild you lvmtab. If you have devices with alternate paths, you will probably have to readd the alternate paths. Check the differences in the before and after files.

...jcd...

[Joseph C. Denman]

Oh....

If you wish to look at your lvmtab,

strings /etc/lvmtab

...jcd...

[Patrick Wallek]

How about just recreating the /dev/vg31 directory and its group file?

# mkdir /dev/vg31
# mknod /dev/vg31/group c 64 x??0000 --->where ?? is a unique minor # for this VG.

Then do:

# vgexport /dev/vg31

That should work for you.
Hopefully!

[Joe Robinson_2]

Thanks again for all who have responded.

I'd thought to simply do mknod, however the physical disk I was using is no longer on the system, therefore I anticipate I'd get 'no such device or address'.

right now we're in the midst of rolling over from one budget year to the next, so I'm not inclined to do anything that would endanger production on the system, but would anticipate that I'll rename the lvmtab and perform a vgscan to see if that will clear the problem. My question is still this, however: if there is no indication of the vg in either the fstab or lvmtab, where is vgdisplay looking to identify this vg on my system?

[Sanjay_6]

Hi Joe,

Have you tried "strings /etc/lvmtab" to see if there is any reference to the missing vg in that file.

Just a thought.

thanks

[Jeff Gyurko]

If you've done just a "vgdisplay -v" and your seeing these errors, you've got this VG defined in your lvmtab. The outlined steps to re-create your lvmtab should fix this. Remember to rename your current lvmtab. If you do not, vgscan will just use this to give you your information, it will not re-create it.

You can also do "vgscan -v -p" to do a preview of the create to see if this will remove the entries for the "problem" VG. Once comfortable that it's removed, do it for real (without -p) after you've renamed the current lvmtab.

J

[Isaac_4]

- The first thing that you should know is the quantity of logical volumes you have in VG to care

the above-mentioned to be able to execute with success the vgimport

- I pass two it is to make the following steps

mkdir /dev/VGNAME

mknod /dev/VGNAME/group c 64 0x0nn0000

vgimport -m /tmp/vgfile -v /dev/vgname /dev/dsk/cxtxdx

The file vgfile can generate it manually and it should contain the following thing according to the quantity of lvols that you had in the VG.
#cat /tmp/vginfo
lvol1
lvol2
lvol3 etc...




vgchange -a and vg01

The file /etc/lvmtab is not necessary to generate it again because when the vgimport this file is executed it is upgraded.

After this to carry out a fsck for each lvol and to verify the consistency of the filesystem