Increase cluster volume group

[Verónica Muñoz Segovia]

Hello,

I'm new in Service Guard, and I would like to how can I increase the space in a volume group?

I already create on the VA7400 a new 5Gb LUN that belongs to the VG Group, but when I type: vgextend /dev/vgdevdbames09 /dev/dsk/c18t2d6, I got the follow error message:

vgextend: IO error on Physical Volume device /dev/dsk/c18t2d6

What are the steps am I need to perform in order to inclease this cluster volume group?

Thanks in advance.

Veronica.

[Hazem Mahmoud_3 · Accepted solution]

Veronica,
Take a look at this thread:
http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=42519

[RAC_1]

Did you do pvcreate on /dev/rdsk/c18t2d6?

If not then do it and do vgextend.

Once vgextend is successful, you will have to reflect the changes on other node.
Do it as follows.

vgexport -psv -m /tmp/vgdevdbsmes.map /dev/vgdevdbames
ftp/sftp/rcp that file to other node.

rm -fr /dev/vgdevdbames/*
mkdir /dev/vgdevdbames
mknod /dev/vgdevdbames/group c 64 "minor_no"
vgimport -psv -m /tmp/vgdevdbames /dev/vgdevdbames

[Oliver Charni]

hi!

You have to do a pvcreate beforce you can import the disk into the volume group.

[Verónica Muñoz Segovia]

I tried to do it, and this is the message:

pvcreate /dev/dsk/c18t2d6
pvcreate: "/dev/dsk/c18t2d6": not a character device.

Also, Am I need to run the same on the alternative lun?

disk 41 0/8/0/0.2.16.0.1.2.6 sdisk CLAIMED DEVICE HP A6A
/dev/dsk/c17t2d6 /dev/rdsk/c17t2d6
disk 42 0/9/0/0.1.16.0.1.2.6 sdisk CLAIMED DEVICE HP A6A
/dev/dsk/c18t2d6 /dev/rdsk/c18t2d6

[Alex Richardson]

Veronica,

The pvcreate command only works on raw device files. Therefor you need to use the device file /dev/RDSK/c?t?d?. Once you have done this you will be able to use the vgextend command to add the disk, this time you will use the standard device file /dev/DSK/c?t?d?.

Now once you have added the new disk to the VG, you will need to use the vgexport -vpsm vgname.map VGNAME to export the VG to a mapfile. You then need to import the new VG configuration on the other node of the cluster which will need to mount this VG.

Please post again if you need assistance with import/exporting the VG's.

[Rajeev Shukla]

Hi you are trying to do pvcreate on block device file /dev/dsk/c18t2d6 where as you need to do pvcreate on character device file i.e /dev/rdsk/c18t2d6 (TAKE NOTE OF "rdsk")
Also you dont need to do pvcreate on alternate path for the same disk.
Once done, you can vgextend and then vgimport the volumegroup in shared mode..i.e
vgexport -v -p -s -m vgtest.map vgtest

and use this map file to import VG on other nodes in the cluster.

[T. M. Louah]

I am assuming that "/dev/dsk/c18t2d6" is the LUN you want to add to volume group /dev/vgdevdbames09 on Node1, to do that you need to run:
0- pvcreate -f /dev/rdsk/c18t2d6 (no need to run it on the Alternate path)
1- vgextend /dev/vgdevdbames09 /dev/dsk/c18t2d6
2- now if you do "strings /etc/lvmtab" or "strings /etc/lvmconf/vgname.conf" should show the LUN you added. if they don't match run "vgcfgbackup -u /dev/vgname"

In SG world, the other node should be aware of the volume group changes the vgexport/vgimport discussed above should do that.

Cheers,
T+