Extending a logical volume beyond dual paths

[Keith Connolly_1]

Hello,

I have a quick question in relation to extending my logical volumes beyond having dual paths

At present I have a 5 node HP-UX cluster in a HA configuration running Veritas Cluster Sever to manage about 50 services/volume groups.

All servers are dual pathed through 2 HBA's & connected to an EMC Symmetrix 3930 array.

In order to migrate our data from the 3930 array to a new EMC DMX-3 array I need all 5 servers to see both sets of storage through 4 HBA's while the data migration occurs

My question is that as all my volume groups have been setup as dual pathed when initially created, when I connect each of the 5 servers
to the new storage via 2 new HBA's the Volume groups will need to be extended beyond dual paths

My question is whther it is possible to extend
a volume group beyond two paths to four by simply vgextending the volume using ...

#vgextend /dev/vgtest /dev/dsk/c12t3d0 /dev/dsk/c10t4d0

#vgextend /dev/vgtest /dev/dsk/c10t4d0 /dev/dsk/c12t3d0

Regards,

Keith

[Ninad_1]

Keith,

You do not esentially need to extend the multiple paths - or PV Links as its called in LVM for the already configured PVs in your VGs. Multiple paths are required only for having redundant paths in case of a link failover.
thus depending on the method you will be using to migrate -
1. If using LVM mirroring [Mirror-UX] - add the new LUNs to the existing VGs and mirror the volumes, then delete the mirror copies from old storage.
2. Add the LUNs as new VGs, create lvols, filesystems, mount then and copy the data across the volumes.

Regards,
Ninad

[sathish kannan]

Keith,
There are lot of software available from EMC for data migration. You can use open migrator to migrate data from one symm to another symm. Talk to your EMC folks and they would be able to help you.

Migrating data from EMC Frame to another EMC frame using open migrator will be easy for you at minimal disturption.


Regards
Sathish