On VG creation and presented disk size

[arkie]

Hi,

We are getting the following message while trying to create a new Volume Group:-

# vgcreate vg01 /dev/dsk/c8t0d1
Warning: Max_PE_per_PV for the volume group (65535) too small for this PV (524031).
Using only 65535 PEs from this physical volume.
Increased the number of physical extents per physical volume to 65535.
vgcreate: Volume group "/dev/vg01" could not be created:
VGRA for the disk is too big for the specified parameters. Increase the
extent size or decrease max_PVs/max_LVs and try again.

c8t0d0 has been presented from EVA4k and the corresponding Vdisk is of size 2047 GB. This is also another discrepancy as the size showing below is 3 TB (4293918720 Kbytes)

# diskinfo /dev/rdsk/c8t0d1
SCSI describe of /dev/rdsk/c8t0d1:
vendor: HP
product id: HSV200
type: direct access
size: 4293918720 Kbytes
bytes per sector: 512

Request for some help on adjusting Max_PE_per_PV or max_PVs/max_LVs to the desired level.

Also, why the difference in size of the aforementioned disk?

[Michal Kapalka (mikap) · Accepted solution]

hi,

you ned to incerase the PE-size = 16 or 32,

there is also lmimitation on the maximum file system size.

mikap

[Michal Kapalka (mikap)]

hi,

check this technical paper :

http://docs.hp.com/en/6054/LVM_Limits_White_Paper_V4.pdf

mikap

[arkie]

Hi Michael,

Understand that Max_PE_per_PV must be increased to 524031 in our case. (524031 X 4 = 2096124) equating to 2046 GB is exactly the size of my LUN.

But, why is the output in diskinfo showing it as 4293918720 Kbytes, which is 3 TB.

[Michal Kapalka (mikap)]

hi,

about the size of your presented disk this will be some speculation / opinion, if you check the HP EVA, how many MB do you have not alocated ??? maybe you made some RAID group that is 3TB and you created virtual LUN with the size 2 TB ??


mikap

[S-M-S]

Hi Arkie,

Try to give PE Size 72 and see what is happening ( vgcreate -s 72 )

[arkie]

Hi Michael/S.M.S

Created VG with `vgcreate -s 32`. But when trying to create a single LV of size 2700 GB, I am getting the below message:-

# lvcreate -L 2764800 -n sapdata3 vg01
lvcreate: Specified LogicalVolumeSize is too large for the PhysicalExtentSize
of the Volume Group. Resulting number of extents is out of the range
1 to 65535 (86400).

[arkie]

Hi Michael,

I have allocated 8166 GB - all Raid5 Vdisks of sizes in GB - 300+60+2047+2047+2047+612+653+200+200. Not all of them have been presented.

Of relevance is a 2047 GB Raid5 Vdisk which has been presented to one of the hosts. In the host, after `ioscan -fnCdisk`, `insf -e`, etc., the diskinfo output for the respective character device file is showing as 4293918720 Kbytes which equates to 3TB. Here is the confusion.

[Michal Kapalka (mikap)]

hi,

Hi Michael/S.M.S

Created VG with `vgcreate -s 32`. But when trying to create a single LV of size 2700 GB, I am getting the below message:-

# lvcreate -L 2764800 -n sapdata3 vg01
lvcreate: Specified LogicalVolumeSize is too large for the PhysicalExtentSize
of the Volume Group. Resulting number of extents is out of the range
1 to 65535 (86400).

try to incerase the PE size to 64

you can not create 2,7 TB lvol, it is depend on the JFS version in your system :

http://docs.hp.com/en/5971-2383/5971-2383.pdf

mikap

[S-M-S]

Hi Arkie,
I have already tolled you to try with PE size 72 :)

In this case, I think you will require atleast minimum of PE size 48

[Michal Kapalka (mikap)]

hi,

i always use this table to know which PE size should i apply.

see attachemnt.

mikap

[chris huys_4]

Hi Arkie,

Interesting.

Following the
"
LVM Version 2.0 Volume Groups in HP-UX 11i v3 (September 2008)
"
pdf file.

url:
http://bizsupport2.austin.hp.com/bc/docs/support/SupportManual/c01919368/c01919368.pdf

A good extent size for a "1.0" volumegroup with sizes between 4 and 8 TB would be 128mb.
(page 21, figure 2)

You didnt mention what OS the problem was occuring on.

The interesting part of youre question is the diskinfo size of 4TB for c8t0d1, as the maximum size of a eva4000 lun is 2TB, following the usersguide of the eva4k. (offcourse due to firmware versions, this could have been enhanced.. )

Reboot the system, see if diskinfo of c8t0d1, still shows a size of 4TB and for good measure do a "dd if=/dev/rdsk/c8t0d1 of=/dev/null bs=1024k" and see what the "number reported is".

If this still all points to a wrong 4TB size, log a software support call with HP support.

Greetz,
Chris

[arkie]

Hi Chris,

We had recently upgraded the EVA XCS firmware version from 6.200 to 6.220. Sorry, forgot to mention - we are using HP-UX 11iv1 and probably LVM version 1 (Major number is 64)

The system has been rebooted, but the size of /dev/rdsk/c8t0d1 is still 4293918720 Kbytes. I did `dd if=/dev/rdsk/c8t0d1 of=/dev/null bs=1024k` but it is still running for the last 2.5 hrs approx

[atul2701]

Pls provide the output of below command

vgdisplay -v vg01

It looks that you have only 2TB space in VG & trying to create LV of 2.7TB size.

Atul

[raghu_14]

Hi,

I want to understand the requirement here.

You have basically have a 4TB disk. But it is not clear how much disk space you would like to use on this disk ? Is it the complete disk ? what is the max size of the logical volume you are planning to create on it ?

In my opinion you may not be able to present the 4TB disk as the pvcreate command on 11i v1 may limit the size to nearly 2TB and may not use the remaining part of it. The max PV size limited is 2TB for 1.0 volume group version.

My suggestion would be to move to 11i v3 March 2008 update, and create 2.0 VGs, and it will work. For 2.x volume group version the max PV size supported is 16TB.

Hope this helps,
Raghu

[atul2701]

Hi Arkie

Raghu is right. LVM version 1.0 is support only 2TB size disks. Even if you are using higher capacity disk LVM will show 2TB size only. LVM 2.0 will support upto 16TB size.

Atul