Using Serviceguard Extension for RAC, 9th Edition, September 2010

# 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.
2. Replace new disk.
The new disk size needs to be of equal or greater size. This is required whether or not the
disk replacement is online or offline.
3. Restore the LVM header to the new disk using the following command:
# vgcfgrestore -n [vg name] [pv raw path]
It is only necessary to perform the vgcfgrestore operation once from any node on the
cluster.
4. Attach PV or Activate the VG from each node of the cluster using the following commands:
#pvchange -a y [pv path]
—OR—
# vgchange -a [y|e|s] [vg name]
The PV must be detached from all nodes and must be attached from each of the nodes to
make it usable. Alternatively, you can reactivate the VG from each of the nodes. (This
command cannot attach all the paths to the PV, therefore each PV link has to be attached as
well.)
NOTE: After executing one of the commands above, any I/O queued for the device will
restart. If the device replaced in step #2 was a mirror copy, then it will begin the
resynchronization process that may take a significant amount of time to complete. The
progress of the resynchronization process can be observed using the vgdisplay(1M),
lvdisplay(1M) or pvdisplay(1M) commands.
Offline Replacement of a Mechanism in an HA Enclosure Configured with Shared
LVM (SLVM)
Hot plugging of disks is not supported for Oracle RAC data that is configured in volume groups
with Shared LVM (SLVM). If you need this capability, you should use disk arrays for your Oracle
RAC data.
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 steps to carry out offline replacement:
1. Make a note of the physical volume name of the failed mechanism (for example, /dev/dsk/
c2t3d0).
2. Deactivate the volume group on all nodes of the cluster:
# vgchange -a n vg_ops
3. Replace the bad disk mechanism with a good one.
4. From one node, initialize the volume group information on the good mechanism using
vgcfgrestore(1M), specifying the name of the volume group and the name of the physical
volume that is being replaced:
# vgcfgrestore /dev/vg_ops /dev/dsk/c2t3d0
Replacing Disks 125