topic Re: corrupted lvmtab in Operating System - HP-UX

corrupted lvmtab

M.J. van der Meer — Wed, 01 Nov 2000 10:56:51 GMT

Hi,

We have a correct /etc/lvmtab; when executing "vgscan -a" we find in the LVM tab a "/dev/". When we remove the /etc/lvmtab and then execute 'vgscan -a' again, we have no /dev/vg00, but still '/dev/', BTW, we have no groupfile in /dev.
Any suggestions?

Re: corrupted lvmtab

Anonymous — Wed, 01 Nov 2000 11:41:56 GMT

had sth like this last weekend after inst of some MC/SG patches. vg00 was still active but vgdisplay vg00 complained
# vgdisplay vg00
vgdisplay: Couldn't query volume group "vg00".
Possible error in the Volume Group minor number; Please check and make sure the
group minor number is unique.
vgdisplay: Cannot display volume group "vg00"

ll /dev/slvmvg #Do you have this one?
#Then try:
mv /dev/slvmvg /tmp
mv /etc/lvmtab /etc/lvmtab.001101
vgscan -v
mv /tmp/slvmvg /dev

We found this using (D=/ or /dev)
614 find $D | while read f
do
if test -c $f
then ll $f | grep 64
fi
done > /tmp/1.t

RGDS
Thomas

Re: corrupted lvmtab

John Palmer — Wed, 01 Nov 2000 11:47:02 GMT

Hi,

Found this support entry:-

The problem is with the /dev/slvmvg file (only with MC/ServiceGuard)
having same major/minor number as /dev/vg00/group file, to verify it
you can type:

#ll /dev | grep 64

To fix it you can do:

mv /dev/slvmvg /tmp
#vgscan
#strings /etc/lvmtab -> now it should be ok

do I need te recreate the /dev/slvmvg ?

When cmlvmd runs, it checks if /dev/slvmvg exists. If not,
it creates one so this file is recreated manually.

But here is the way te re-create it manually if you want:

Recreate the special file:

#mknod /dev/slvmvg c 64 0x0

Change the file mode:

#chmod 660

This is a known problem that has no permanent fix available yet.

Hope this helps,
John

Re: corrupted lvmtab

M.J. van der Meer — Wed, 01 Nov 2000 12:23:38 GMT

Hi,

Indeed, your sugesstions worked, but when excuting 'vgscan' again, we have the same problem, '/dev/' (without vg00).
Any other solutions?

Martijn

Re: corrupted lvmtab

Anonymous — Wed, 01 Nov 2000 15:02:11 GMT

"your suggestions worked":
ie we CAN create a "good" lvmtab WHEN /dev/slvmvg moved out of the way?

PS: points always appreciated- useful to get an idea on quality of an answer...

Re: corrupted lvmtab

MARTINACHE — Thu, 02 Nov 2000 09:09:09 GMT

I have the same problem and I can regenerate a good lvmtab whithout /dev/ .

But /dev/vg00 is not the first volume group in the /etv/lvmtab file.

I remember that it should cause some problem when booting ?

Re: corrupted lvmtab

M.J. van der Meer — Thu, 02 Nov 2000 11:49:24 GMT

Thank you all for the quick answers and since this is a known problem, we have to live with it for the time being.

Martijn

Re: corrupted lvmtab

John Palmer — Thu, 02 Nov 2000 12:03:20 GMT

Hi,

As a matter of interest, why are you running vgscan? It's normally only run (as the man pages state) 'in the event of a catastrophic error'.

I have several systems where the root volume group is not the first in lvmtab (some that don't have a vg00 at all) and have never experienced any problems booting.

Regards,
John