topic Re: Create LV on shared VG in Operating System - HP-UX

Create LV on shared VG

Filosofo — Mon, 26 May 2003 09:54:57 GMT

Hello,
I must add a new LV on a vg_pippo, that is activate in shered mode (2 partition of Super Dome with oracle Rac).
I read on man lvcreate that:
lvcreate cannot be performed if the volume group is activated in shared mode.
The only way to add a LV is stop the packages, execute
create LV
export and import of vg_pippo

I hope that there is another way for make this operatio without stop packages.
Please help me.

Thanks

Filo

Re: Create LV on shared VG

T G Manikandan — Mon, 26 May 2003 10:00:37 GMT

You cannot perform that without bringing down the package.

You need to bring down the package.

Thanks

Re: Create LV on shared VG

Radhakrishnan Venkatara — Mon, 26 May 2003 10:02:59 GMT

If this is the case and the VG's are activated in shared mode, vgchange -a s mode, then the simple answer is no, you cannot lvextend the lv's while the VG is activated.

radhakrishnan

Re: Create LV on shared VG

Radhakrishnan Venkatara — Mon, 26 May 2003 10:04:05 GMT

sorry for putting lvextend it is lvcreate

check this link

http://forums.itrc.hp.com/cm/QuestionAnswer/1,,0xb6e1e822e739d711abdc0090277a778c,00.html

radhakrishnan

Re: Create LV on shared VG

Rajesh G. Ghone — Mon, 26 May 2003 10:11:03 GMT

Sorry Filo you cannot create LV when the VG is mount in a shared mode,the only way is to bring down the package & do it offline.

Regards,
Rajesh G.

Re: Create LV on shared VG

Jean-Louis Phelix — Mon, 26 May 2003 10:54:15 GMT

Hi,

I'm sorry, but only sam doesn't want to do it. This is I assume only to try to preserve integrity of your cluster. If you want to do it manually, you will have some more steps under your own responsability :

- you have to export/import the vg on other cluster nodes (but for a single LV with no new disk a mknod would be enough ...)

- you have to mount the lvol manually (because package is already running)

- you have to modify the control scripts to make them mount and umount the new lvol

Regards.

Re: Create LV on shared VG

Michael Steele_2 — Mon, 26 May 2003 12:08:27 GMT

Although LVM will allow you to run shared commands when the package is up, the shared vgs will remain separate from the package until added. Use these LVM commands to activate shared vgs for testing purposes before the MC/SG work only:

vgchange -S y -c y /dev/vg##
vgchange -a s /dev/vg##

To add new LVM structures into a ServiceGuard package the package.conf file has to be updated and 'cmmakpkg -p' has to be rerun. This is because LVM is not controlled through the O/S but the SG binaries, which have to be updated and restarted.

Shared logical volumes are 'updateable' from every node simultaneously and require a lot more then just LVM to work. At least one asynchronous device driver is needed, different values of kernel parameters, special versions of EMS, MC/SG and Oracle, its a complicated procedure. Attach 'cmviewcl -v' and 'cmscancl' to begin with, as well as the LVM work you'd like to accomplish.