reducing a disk from the volume group

[sheevm]

We have a volume group has one big one logical
volume size of 25GB. It has three 9gb drives.
It is a vxfs file system and about 8GB data is in the filesystem.

I want to remove one of the drives. Do I have to do lvreduce and vgreduce? If I do that is the existing data is safe? I want to retain the data without going thru restoring from the backup.

What is the best way to do this?

Thanks for the help

[Christopher McCray_1]

Hello,

You also have to shrink the size of the rlvol and, unless you have OnlineJFS, you will have to run newfs, which destroys the data and you will have to restore from backup.

Chris

[Bill McNAMARA_1]

use the pvmove command to move the lv off the drive you want to vgreduce out of the vg.

lvreduce is only a good idea if you have
a> backed up
b> defragged the filesystem

You need onlineJFS to do a.

Otherwise, backup fs, lvremove, lvcreate new size. Then pvmove.

You can find out what lvs are on the disk with lvdisplay -v and/or pvdisplay -v.

Later,
Bill

[Hai Nguyen_1]

It depends on the way you have configured the volume. Can you post "vgdisplay -v /dev/vg_volume_name?

Hai

[Deshpande Prashant]

HI
You will have to have the Online JFS to reduce the VG/LV on fly.
Before reducing LV/VG, defrag the LV and keep backup of your data.
With out Online JFS, you will have to backup your data delete the existing LV and re-create the LV of desired size.

Thanks.
Prashant Deshpande.

[sheevm]

hai Nguyen:

Here is vgdisplay output. This logical volume is 25gb. and in production. I cannot afford to take time in restoring process. I need to remove one of the drives from this logical volume keeping the data safe.

If I do the pvmove can I reduce that drive from the volume group?

See the attached vgdisplay output.

Thanks

[Victor_5]

Are you using mirroring? What is your current value of mirror copy?

[sheevm]

Victor:

These drives are not mirrored.
Thanks

[Hai Nguyen_1]

Raji,

I think Online JFS is the only choice for you now.

Can you run the following command and post the output. If the output means this FS is not really busy, I may have a solution for you.
# fuser -cu /

Hai

[sheevm]

Hai:

This time file system is getting used. When I am ready to do this the file syste will not be in use. So PLEASE GIVE ME THE TRICK.

Thanks

[MANOJ SRIVASTAVA]

Hi Raji


There is ac onfusion here in the vgdisplay o/p there are only 55 PE which are free ie you ahve about 200 mb free space where as you have stated that there is only 8gb used , If the o/p is of the volume group you want to remove first you need to reduce the data as all the 3 disks have nearly 100 % utilization. After teh data is removed or tarred then depending on which volume it frees it can be possible to remove the disk

Manoj Srivastava

[Hai Nguyen_1]

Raji,

This time file system is getting used. When I am ready to do this the file syste will not be in use. So PLEASE GIVE ME THE TRICK.

Here is what I think can work.
Assumptions:
- A is the current FS on which /dev/vg07/lvol1 is mounted.
- B is an existing FS which has more than 8GB empty disk space.
- A has STATIC data.

With the assumptions above, here are the sequence

# mkdir /B/A
# cp -pR /A/* /B/A
# umount /A (only when A is not busy)
# rmdir /A
# ln -s /B/A /A (this will behave as the original A now.)
# lvremove -f /dev/vg07/lvol1
# vgreduce /dev/vg07 /dev/dsk/c4t1d2
# use SAM to recreate /dev/vg07/lvol1 with /A_temp as a mount point.
# cp -Rp /B/A/* /A_temp
# rm /A (it is only a soft link. Do this when it is not busy only)
# mv /A_temp /A
# vi /etc/fstab to change /A_temp to /A
# rm -r /B/A
# done

Hai

[Victor_5]

I prefer you use the standard steps,

lvreduce --> vgreduce --> pvmove.

[sheevm]

Hi Guys:

Thanks for the help. I want to ssign points for some reason that button is disappered "assign points". Can you tell me what is wrong?

Thanks

[Christopher McCray_1]

Hello again,

It is possible that your seesion has logged out from underneath you. Log out and log back in and see if this helps.

Regards

Chris

[sheevm]

Hi Guys:

Still I cannot get "assign points" button after logging out and logging in. Please do not think I am ignoring to assign points.


Thanks