topic Re: I can't increase my logical vloume in Operating System - HP-UX

I can't increase my logical vloume

gangyi wei — Mon, 28 May 2001 07:14:50 GMT

1.I use HP UX 10.20
2.i have this volume group:
--- Volume groups ---
VG Name /dev/vgom
VG Write Access read/write
VG Status available, exclusive
Max LV 255
Cur LV 2
Open LV 2
Max PV 16
Cur PV 6
Act PV 6
Max PE per PV 1024
VGDA 12
PE Size (Mbytes) 4
Total PE 6138
Alloc PE 3784
Free PE 2354
Total PVG 0
i have free PE 2354
3.lvdisplay /dev/vgom/lvom
--- Logical volumes ---
LV Name /dev/vgom/lvom
VG Name /dev/vgom
LV Permission read/write
LV Status available/syncd
Mirror copies 1
Consistency Recovery MWC
Schedule parallel
LV Size (Mbytes) 7168
Current LE 1792
Allocated PE 3584
Stripes 0
Stripe Size (Kbytes) 0
Bad block on
Allocation PVG-strict

4.But i can't increase space for lvom.
thank you very much!

Re: I can't increase my logical vloume

Thierry Poels_1 — Mon, 28 May 2001 07:45:36 GMT

hi,
can you give us the exact error message?
I can imagine a few problems:
- you are mirroring lvom, maybe there is no free space enough on one disk for mirroring.
- maybye lvom is in use, and cannot be unmounted
...
regards,
Thierry.

Re: I can't increase my logical vloume

Vincent Stedema — Mon, 28 May 2001 07:55:08 GMT

How much space are you trying to add to the lv? As it's mirrored, you can only increase the lv by half of the Free PE. In your case, you can only increase the lv by 2234/2 = 1117.

Regards.,
Vincent

Re: I can't increase my logical vloume

gangyi wei — Mon, 28 May 2001 07:58:34 GMT

thank you!
yes,lvom is mirror.
but i have two 4G disk free.
I can't increase only 100M space.
sorry my poor english.

Re: I can't increase my logical vloume

KapilRaj — Mon, 28 May 2001 08:17:10 GMT

hi ,

which command r u using for this ?.

lvextend -L ABCD /dev/vgXX/lvolYY

where ABCD is the expected size pf the lvol.

kaps

Re: I can't increase my logical vloume

Vincent Stedema — Mon, 28 May 2001 08:17:28 GMT

What surprises me is that the allocation policy for lvom is set to PVG-strict, but according to the info you provided your volume group doesn't have any PVG's. This might explain why you can't extend the lv.

You might want to use lvchange to set the allocation policy from "PVG-strict" to "strict".

Hope this helps.

Vincent

Re: I can't increase my logical vloume

Ravi_8 — Mon, 28 May 2001 08:59:54 GMT

vincent point is also true, another reason might be he might have specified contoguous allocation for that vg.
without error message it is difficult to say

Re: I can't increase my logical vloume

Wieslaw Krajewski — Mon, 28 May 2001 18:42:11 GMT

Hi,

Vincet seems to be close to the right answer.

But why I answer close to be right?

What is strange for me is that you have mirrored LV with PVG-strict allocation policy and there is no physical volume groups defined. At least this results from the info
in your question.

So try to change your allocation policy running

lvchange -s y /dev/vgom/lvom

to change allocation policy into strict.
If needed and reasonable can use -s n
This allows mirrored copies are on the same disk.

Rgds.

Re: I can't increase my logical vloume

gangyi wei — Mon, 28 May 2001 23:18:21 GMT

Thanks all.
I will try.

Re: I can't increase my logical vloume

meg_2 — Tue, 29 May 2001 02:29:58 GMT

hello, i m gangyi's colleague.
the following is steps and error messages when we try to increase volume size:

#cmhaltpkg openmail
//umount filesystem on vgom

# vgchange -c n vgom
Performed Configuration change.
Volume group "vgom" has been successfully changed.

# vgchange -a y vgom
Volume group "vgom" has been successfully changed.

# lvextend -L 8000 /dev/vgom/lvom
lvextend: Not enough free physical extents available.
Logical volume "/dev/vgom/lvom" could not be extended.

what's wrong?

Re: I can't increase my logical vloume

Thierry Poels_1 — Tue, 29 May 2001 05:24:36 GMT

Hi,
"lvextend: Not enough free physical extents available."
check both disks for free space:
pvdisplay /dev/dsk/cxtxd0
and check "Free PE"; you will need space on both disk as you are using mirroring.
good luck,
Thierry.

Re: I can't increase my logical vloume

Satish Y — Tue, 29 May 2001 06:05:02 GMT

Hi,

All the steps are correct. But, As vincent said you can only increase the lv by 1177PE (2234/2), i.e., 4708MB (1177*4), because you have mirrored your logical volumes and you can use only half of the available PE.
But, you are trying to increase by 8000 MB(8 GB), you need to add anothe 4GB disk to your VG to do it.

Hope it is clear.

Cheers...
Satish.

Re: I can't increase my logical vloume

meg_2 — Tue, 29 May 2001 23:07:11 GMT

yes, very clear, many thanks^_^

now we have extended lv successfully without umounting filesystems on vgom

as app on vgom is very important, will can't umount until this weekend

by the way, should we have to backup the whole things in vgom before we extending filsystem? It may take considerable time, but we hope we can make it as soon as possible