Extend Stripped LV


Extend Stripped LV

Hi Friends,

Can some one let me how to extend Stripped LV.

/dev/vg01/lvol2 - LV i want to extend, I have added one Disk of same Size.

When i try to do lvextend.
uksp19 # lvextend -L 18000 /dev/vg01/lvol2
Warning: rounding up logical volume size to extent boundary at size "18048" MB for striping.
lvextend: Not enough free physical extents available.
Logical volume "/dev/vg01/lvol2" could not be extended.
lvextend: Couldn't retrieve the list of the physical volumes
belonging to volume group "/dev/vg01".
Failure possibly caused by strict allocation policy

My VG/LV details are..

uksp19 # lvdisplay -v /dev/vg01/lvol2 |more
--- Logical volumes ---
LV Name /dev/vg01/lvol2
VG Name /dev/vg01
LV Permission read/write
LV Status available/syncd
Mirror copies 0
Consistency Recovery MWC
Schedule striped
LV Size (Mbytes) 10112
Current LE 2528
Allocated PE 2528
Stripes 32
Stripe Size (Kbytes) 1024
Bad block NONE
Allocation strict
IO Timeout (Seconds) default

uksp19 # vgdisplay -v vg01 |more
--- Volume groups ---
VG Name /dev/vg01
VG Write Access read/write
VG Status available, exclusive
Max LV 255
Cur LV 7
Open LV 7
Max PV 200
Cur PV 54
Act PV 54
Max PE per PV 2178
VGDA 108
PE Size (Mbytes) 4
Total PE 117558
Alloc PE 115381
Free PE 2177
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0

The disk which was added to VG is :

PV Name /dev/dsk/c3t15d4
PV Name /dev/dsk/c5t15d4 Alternate Link
PV Status available
Total PE 2177
Free PE 2177
Autoswitch On

could someone help me to resolve this issue !

Many Thanks!!
Robert-Jan Goossens
Honored Contributor

Re: Extend Stripped LV


Stripes 32
Stripe Size (Kbytes) 1024

You have striped this logical volume over 32 disks! In order to extend the volume you need to add 32 disks.

more info.
lvextend: Not enough free physical extents available


Honored Contributor

Re: Extend Stripped LV

I would suggest to backup the LV, recreate the LV with stripeda across 4 or 8 disk.Also you may SKIP the striping itself as the SAN disk/LUN may be stripped at SAN level itself for performance.
Trusted Contributor

Re: Extend Stripped LV

You need to off the stripping .see lvchange man pages..
then you can extend the lv.

Otherwise take backup of the lv and recreate without striping.
Hein van den Heuvel
Honored Contributor

Re: Extend Stripped LV

Manojit Das>> Are you sure you can disable striping for an lv? You can disable the 'distributed allocation policy', but not striping best I know.

As others indicated, you need some space on each of the 32 volumes for this extent to work. This is why is mentions the 'rounded up to 18048. That 18048 is evenly divisible by 32.
However, it looks like the only free space is on the added disk, so that's not going to work.
As indicated, you'll have to delete and recreate the LV, but the IO distribution will likely become lousy, which may or might not be an issue.

Is any of the other 6 LV's less important/critical and also striped?
Maybe you can relocate that to make free space for the attempted extend.

Good luck!