service guard

[juan ramos_1]

Hi all.
I want to add a new disk to a volume group to mirror a logical volume, this volume group is under a cluster. can I do this while the package is runnin ?
Thanks all

[John Poff]

Hi,

Sure you can. You can do all kinds of LVM work on a volume group in MC/SG while packages are running.

JP

[Sundar_7]

You may not be able to do all kind of LVM activities when the package is up. For ex, if you have to remove and recreate a logical volume that a package uses and if the package has been written to monitor the availablity of the mount points, you will have to carry out some additonal steps.

In your case, you can add the new disk to the volume group on the fly, without having to halt the package

1) pvcreate the disk
2) Extend the VG
3) Mirror the LV
4) Create a map file of the VG using vgexport
5) Copy the map file over to any adoptive nodes for the package.
6) In the adoptive nodes,export the VG and import them.

- Sundar

[Steven E. Protter]

mirroring can be done while the package is running. There may be a peformance hit during the logical volume copy.

lvextend -m 1

SEP

[Geoff Wild]

Yes you can...

For more info, see chapter "7 Cluster and Package Maintenance ", section "Reconfiguring a Cluster" of "Managing Serviceguard":

http://docs.hp.com/hpux/onlinedocs/B3936-90079/B3936-90079.html

That lists changes you can do to both a running and halted cluster.

Rgds...Geoff

[Prashant Zanwar_4]

There shall not be any problem as far as you are adding a new disk and you can probe it on the server. Once you see the disk, you can do as you wish, putting in VG, lvextend, or lvcreate, put the defination in the package control file, if it is a new application you are planning to install, follow application steps, like if it requires reboot or so.

You have to transfer the new-create defination to adoptive nodes also..that you can do using vgexport and vgimport and also put the same in failover scripts or something of that kind you are using..

While creating, make the lvol cluster aware..

If you have a deifnation in package control script, you next reboot shall activate the LV correctly. .

Hope this helps
Prashant

[juan ramos_1]

Thanks all for your fast answaer