topic Re: Problems with LVM in Operating System - HP-UX

Problems with LVM

Bob Gulien — Thu, 30 Jun 2005 02:30:38 GMT

Hi,

I try to extend a VG (HP-UX 10.20) with a unused disk.
I see that the disk (in lvmtab) is claimed by a vg that doen't exist anymore.
I try all the solutions from the Knowledge Base.
When I do the necessary commands, like vgreduce, vgcreate, vgexport vgchange it comes back with the error:
Cannot open the control file "/dev/vghist/group"
I couldn't find a solution to this in the KB.
Maybe one of you can help me?

regards,

Bob Gulien

Re: Problems with LVM

Thayanidhi — Thu, 30 Jun 2005 02:36:37 GMT

Are trying to extend the VG "vghist"?
If yes then activate the VG first with vgchange -a y /dev/vghist

If you are creating a new VG (vghist) then you first create the group file with mknod command using unigue vg-id.

If you need more help on this revert.

REgds
TT

Re: Problems with LVM

santosh jha — Thu, 30 Jun 2005 02:59:47 GMT

Please give more information.

Paste output of vgscan ,ioscan and ll /dev/vghist commands.

Thanks

Santosh Jha

Re: Problems with LVM

Sarjerao — Thu, 30 Jun 2005 03:30:30 GMT

do u mean in lvmtab, disk is in histvg ?
if yes there should be /dev/histvg/group control file. If it is not there create it using mknod command. check permission,owner and group if file exists.
Then remove using vgexport or vgremove.
But if u have to use vgremove, u have to first all lv associated to that vg and then vgreduce.

Re: Problems with LVM

Shyjith P K — Thu, 30 Jun 2005 04:54:15 GMT

Hi,

Can you try to rename the /etc/lvmtab file and then recreate it using "vgscan"?

# mv /etc/lvmtab /etc/lvmtab.old
# vgscan -a -v

After this check whether you can see the disk in /etc/lvmtab.
If not, do a pvcreate and then extend the VG.

Rgds
Shyjith

Re: Problems with LVM

Bob Gulien — Thu, 30 Jun 2005 05:24:16 GMT

The thing is that I have a VG called hist.
There was however in the past a VG called vghist.
It was removed by my predecessor. I guess not the right way.
Anyway, I want to add the unused disk to the VG hist. But in the lvmtab file the disk is still as used by vghist.
So I tried to reinstate vghist with vgcreate etc.
That didn't work.
So I did it the way Sarjerao suggested.
But the persistent error I get is:

venus:/etc# vgchange -a n vghist
vgchange: Warning: couldn't query physical volume "/dev/dsk/c1t2d0":
The specified path does not correspond to physical volume attached to
this volume group
vgchange: Warning: couldn't query all of the physical volumes.
vgchange: Couldn't deactivate volume group "vghist":
Device busy

Any idea's on that one?

Re: Problems with LVM

Thayanidhi — Thu, 30 Jun 2005 06:21:37 GMT

Is vghist is active now? (check with vgdisplay /dev/vghist)
If no mv the /etc/lvmtab to some thing else and run vgscan.
If yes how many disks on that vg?

Revert

Regds
TT

Re: Problems with LVM

Shyjith P K — Thu, 30 Jun 2005 06:29:19 GMT

Hi Bob,

I am bit confused? Are you trying to extend the VG "/dev/hist" ?
Is there a directory called "/dev/vghist" exists? If not could you pls try recreating /etc/lvmtab?

Rgds
Shyjith

Re: Problems with LVM

PVR — Thu, 30 Jun 2005 06:43:57 GMT

Hi Bob !

Try by exporting the VG vghist.

first do it in the preview mode.

If that also doesn't work, keep a copy of lvmtab and recrate lvmtab file. This should solve your problem.

Re: Problems with LVM

Bob Gulien — Thu, 30 Jun 2005 08:47:59 GMT

Thanks for all the suggestions.
I have tried the vgscan option, but I get an error from this too:

venus:/etc# vgscan -a -p

Pid 323 received a SIGSEGV for stack growth failure.
Possible causes: insufficient memory or swap space,
or stack size exceeded maxssiz.
Memory fault(coredump)

So I have to solve this first. It's an opld machine (D250) an not too much memory, but an important app. on it.

I know a lot more. Again thanks.

Re: Problems with LVM

Thayanidhi — Thu, 30 Jun 2005 09:17:46 GMT

Look like there is some thing running out.

How much memory you have?

grep -i physical /var/adm/syslog/syslog.log

what is the current swap size?

swapinfo

What the current kernel parameters?

sysdef

There would file called "core" where you run the vgscan. run 'what core'

Revert
TT

Since you are telling its old hardware but very important application running, be slow in your approach.

Re: Problems with LVM

Thayanidhi — Thu, 30 Jun 2005 09:18:29 GMT

Also
ulimit -a

Re: Problems with LVM

Bob Gulien — Fri, 01 Jul 2005 01:53:35 GMT

Hi TT,

The machine is a 101 Mhz, 256 Mb mem. machine.
Swapspace is 512 Mb.

This is the result of what core and ulimit -a.

sdysdef is an attachement.

venus:/etc# ulimit -a
time(seconds) unlimited
file(blocks) unlimited
data(kbytes) 125000
stack(kbytes) 8192
memory(kbytes) unlimited
coredump(blocks) 4194303
nofiles(descriptors) 1024
venus:/etc# what core
core:
$Revision: 78.57.1.1 $ MIRROR PRODUCT
PATCH-PHCO_20441 for 10.20; for 10.30, 11.x compatibility libc.1_ID@@/main
/r10dav/libc_dav/libc_dav_cpe/9
/ux/core/libs/libc/shared_pa1/libc.1_ID
Nov 10 1999 10:53:12
SMART_BIND
92453-07 dld dld dld.sl B.10.32 990202
venus:/etc#

Thanks,

Bob