CentOS / RHEL : How to migrate storage (LVM) with pvmove Command

Solution:
Existing Configuration :

Existing Physical Volume: 1.5 TB, /dev/mapper/mpathX
Existing Volume Group: data_vg
Existing Logical Volume: lv_data01 (/dev/mapper/data_vg-lv_data01)

We need to move to the following configuration :

Physical Volume: 1.5TB, /dev/mapper/mpathY
Volume Group: data_vg
Logical Volume: data (/dev/mapper/data_vg-lv_data01)

Steps

1. Begin by pvcreate’ing the new disk. This is the disk from the new storage array to which we want to migrate to.

# pvcreate /dev/mapper/mpathY

2. Now, add this disk into the data_vg Volume Group :

# vgextend data_vg /dev/mapper/mpathY

Make sure there are free extents on the new disk, before running pvmove

3. Begin the migration from the /dev/mapper/mpathX PV to the new /dev/mapper/mpathY PV

# pvmove -b /dev/mapper/mpathX /dev/mapper/mpathY

This will take time based on size to complete the activity. -b option in the command above runs the pvmove command in background.

4. Periodically, you can check the progress of the migration, Make sure you’re looking in the “Copy%” column for the LV and VG that you’re working with.

# lvs -a -o+devices

When the migration is completely finished, you will know because the “Copy%” column will no longer register a value for the LV and VG that you’re working in.

You may also run pvmove -iX , where X is an interval in seconds to report the progress. For example, pvmove -i5 will report progress every 5 seconds.

5. Now, you can safely remove the original PV from the VG.

# vgreduce oracleprod /dev/mapper/mpathX
# pvremove /dev/mapper/mpathX