[CentOS] LVM - pvmove and multiple servers

Sat Jan 10 13:13:53 UTC 2015
Daniel Hoffman <centos at a20me.com>

Hi All.

Looking for some guidance/experience with LVM and pvmove.

I have a LUN/PV being presented from a iscsi SAN. The LUN/PV is presented
to 5 servers as a shared VG they all have LV's they use for data, they are
all connected via iSCSI.

As the SAN I am using is being replaced I need to move onto a new unit.

My migration strategy at this time is to

1. Present a new LUN from the new SAN to all machines.
2. Make a PV with the new LUN.
3. Add it to the existing VG.
4. Use pvmove to move all the data from one PV to another.
5. Once the old LUN is empty, complete a pvresize to remove the old LUN.

This all seems sound but looking for advice, specifically around the fact
that the VG/PV data is being used by a number of machines/servers and the
LV's are active on a number of different nodes.

All the documentation/examples I can find assume a disk in a server, not a
LUN on a SAN being shared by a number of servers.

Any advice is appreciated.