Using Serviceguard Extension for RAC, 5th Edition, June 2007

Maintenance and Troubleshooting
Replacing Disks
Chapter 4228
Online Replacement of a Mechanism in an HA
Enclosure Configured with Shared LVM (SLVM)
If you are using software mirroring for shared concurrent activation of
Oracle RAC data with MirrorDisk/UX and the mirrored disks are
mounted in a high availability disk enclosure use the following LVM
command options to change/replace disks via OLR (On Line
Replacement):
NOTE This procedure supports either LVM or SLVM VG and is “online”
(activated), which uses an “online disk replacement” mechanism. It is
supported for SLVM, however the PV being replaced must be detached
from each node. For example, running pvchange -a N /dev/dsk/… from
one node only detaches the disk from that node's perspective.
1. Detach the target PV by using one of the following commands on
each node of the cluster:
# pvchange -a n [pv path]
Use the pvchange command -a n [pv path] to detach only one path
or replace a disk if the primary path disk path is not performing well
and you want to disable the path. The pvchange -a n command
detaches the single specified PV Link (device path). (If the path was
the path in use LVM will switch to any alternate PV Link that is still
available.)
OR
# pvchange -a N [pv path]
Alternatively, use the pvchange -a N [pv path] command to
detach a disk (all paths to the disk) and close it. Use this to allow
diagnostics or replace a multi-ported disk.
NOTE If the volume group is mirrored, applications can continue accessing
data on mirror copies after the commands above. If the volume is not
mirrored, then any access attempts to the device may hang
indefinitely or time out. This depends upon the LV timeout value
configured for the logical volume.