Error extending a LV on a ServiceGuard FS.

[Nuno Ricardo Carvalho]

Hi guys, I have a problem extending a LV on my system. This LV is under ServiceGuard control, and everytime I try to extend it returns the folowing error:

GDOCLCS1 > lvextend -L 235000 /dev/gdoc_fndocs0/fn_docs0
lvextend: Not enough free physical extents available.
Logical volume "/dev/gdoc_fndocs0/fn_docs0" could not be extended.

Here goes the output of VGdisplay:

vgdisplay /dev/gdoc_fndocs0
--- Volume groups ---
VG Name /dev/gdoc_fndocs0
VG Write Access read/write
VG Status available, exclusive
Max LV 255
Cur LV 1
Open LV 1
Max PV 16
Cur PV 7
Act PV 7
Max PE per PV 25003
VGDA 14
PE Size (Mbytes) 4
Total PE 113238
Alloc PE 57678
Free PE 55560
Total PVG 0
Total Spare PVs 0
Total Spare PVs in use 0

And LVDisplay:

GDOCLCS1 > lvdisplay /dev/gdoc_fndocs0/fn_docs0
--- Logical volumes ---
LV Name /dev/gdoc_fndocs0/fn_docs0
VG Name /dev/gdoc_fndocs0
LV Permission read/write
LV Status available/syncd
Mirror copies 0
Consistency Recovery MWC
Schedule parallel
LV Size (Mbytes) 230712
Current LE 57678
Allocated PE 57678
Stripes 0
Stripe Size (Kbytes) 0
Bad block on
Allocation PVG-strict
IO Timeout (Seconds) default

Recently I added 4 disks, I need to extend a LV under this VG.
Can anyone help? TIA.

[Sundar_7 · Accepted solution]

hmm..I dont see anything obviously wrong with the LV/VG display. Only thing I could think of is to remove the "PVG-strict" allocation and try it again. Not sure if this is going to help but for sure not going to hurt

# lvchange -s n /dev/gdoc_fndocs0/fn_docs0

# lvextend -L 235000 /dev/gdoc_fndocs0/fn_docs0

[Jeff_Traigle]

You're using physical volume groups according to the allocation policy on your LV. I haven't done much with them, but could it be that you didn't extend the VG to these new PVs with the -g option?

[Nuno Ricardo Carvalho]

Hi, thanks for the quick answer.

Do you know if the 'vgchange' command will cause any hang acessing the VG/LV?

Thanks again.

[Sandman!]

Could you post the contents of /etc/lvmpvg.

# cat /etc/lvmpvg

[Michael Steele_2]

Examine the contents of /etc/lvmpvg and update with the new disks if in use. Can you paste in /etc/lvmpvg?

1) vgextend -g pvg /dev/vg## /dev/dsk/....
2) lvextend -m /dev/vg##/lvol# /dev/dsk/... pvg#
3) vi /etc/lvmpvg (* manually add in new disks)

[Nuno Ricardo Carvalho]

Here goes the lvmpvg:

GDOCLCS1 > cat lvmpvg
VG /dev/vg00
PVG PVG00A
/dev/dsk/c1t2d0
PVG PVG00B
/dev/dsk/c2t2d0

[Nuno Ricardo Carvalho]

Sundar! Funtastik.

That's it, Problem solved, two last qustion, should I return the VG to PVG Strict Setting?? Is it possible to raise the logical extents maximum? also near the top

Since this volume is user by a ServiceGuard Cluster...

Thanks again.

[Sandman!]

Well you should leave the PVG-strict allocation policy off otherwise you will encounter the same problem later on, when extending lvols.

There is nothing like a max logical extents, there is only max physical extents. The value of max PE is set when the VG is created and can only be changed by removing the VG and recreating it.

[Nuno Ricardo Carvalho]

Not shure of that:

GDOCLCS1 > lvextend -L 280000 /dev/gdoc_fndocs0/fn_docs0
lvextend: "LogicalExtentsNumber" is bigger than the maximum value allowed.

I think this is the set value when creating the LV, right?

Thanks.

[Sundar_7]

Hi,

The following error message means you are trying to allocate more than 65535 (hard limit) PEs to the LV. (i.e 28000 > 65535 * 4 )

lvextend: "LogicalExtentsNumber" is bigger tha the maximum value allowed.

Now with the current configuration, you cannot allocate more than 65535 PEs to your LV. I believe the only way to work around this limitation is to recreate the VG with bigger PE size.

Sundar

[Sundar_7]

As far as the PVG-Strict goes, it is only useful in the following cases

* If you want to mirror the volumes across the controllers(i.e when you dont want to mirror the volume to a physical disk that is connected to the same HBA as the primary one).

* If you use the distribution allocation for the LV, which you dont.

So, you can leave it off.

[Nuno Ricardo Carvalho]

Managed to expand the LV in question just for changing the PVG Strict setting to Non Strict.

Gracias. :)