Online disk remove.

[Tanmay_1]

I have a vg with 2 device. I wish to remove one device and add one new device on line. Can I use pvmove option to do it? If yes can a pvmove command runs on MCSG VG?

Tanmay

[Sridhar Bhaskarla · Accepted solution]

Hi Tanmay,

Yes. But there is a little risk associated with pvmove. So I would try for mirror extend/reduce method than pvmove if possible. What you have to do is

1. add the new disk to the VG.

pvcreate /dev/rdsk/cxtydz
vgextend vgxx /dev/dsk/cxtydz

2. Extend the mirrors and break the mirrors

lvextend -m 1 /dev/vgxx/lvol1 /dev/dsk/cxtydz
lvreduce -m 0 /dev/vgxx/lvol1 /dev/dsk/cutvdw

If the logical volumes are spread across multiple disks of which you are only going to replace one, then you can't use mirror process. Use 'pvmove' but make sure you don't break it in between.

pvmove /dev/dsk/cutvdw /dev/dsk/cxtydz

will move all the physical extents from cutvdw to cxtydz

This can be done online when the cluster is running. However, you will have to export/import the VG on on the other node using the latest map files on the node where you did the maintenance.

-Sri