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

Maintenance and Troubleshooting
Managing the Shared Storage
Chapter 4216
# vgchange -a e -x vg_shared
NOTE Ensure that none of the mirrored logical volumes in this volume
group have Consistency Recovery set to MWC (refer lvdisplay(1M)).
Changing the mode back to “shared” will not be allowed in that case,
since Mirror Write Cache consistency recovery (MWC) is not valid in
volume groups activated in shared mode.
5. Make the desired configuration change for the volume group on the
node where the volume group is active, run the required command to
change the configuration. For example, to add a mirror copy, use the
following command:
# lvextend -m 2 /dev/vg_shared/lvol1
6. Export the changes to other cluster nodes if required.
If the configuration change required the creation or deletion of a new
logical or physical volume (i.e., any of the following commands were
used - lvcreate(1M), lvreduce(1M), vgextend(1M),
vgreduce(1M), lvsplit(1M), lvmerge(1M) then the following
sequence of steps is required.
a. From the same node, export the mapfile for vg_shared. For
example
# vgexport -s -p -m /tmp/vg_shared.map vg_shared
b. Copy the mapfile thus obtained to all the other nodes of the
cluster.
c. On the other cluster nodes, export vg_shared and re-import it
using the new map file. For example,
# vgexport vg_shared
# mkdir /dev/vg_shared
# mknod /dev/vg_shared/group c 64 0xhh0000
# vgimport -s -m /tmp/vg_shared.map vg_shared
CAUTION If Business Copies, or Business Continuity Volumes (BCs or BCVs)
are in use, then run vgchgid(1M) before starting the procedure.