Using Serviceguard Extension for RAC, 8th Edition, March 2009

the volume group must be halted. This procedure is described in the Managing Serviceguard
Sixteenth Edition user’s guide Appendix G.
Initializing Disks for CVM
Initialize the physical disks that will be employed in CVM disk groups. If a physical disk has
been previously used with LVM, you should use the pvremove command to delete the LVM
header data from all the disks in the volume group (this is not necessary if you have not previously
used the disk with LVM).
To initialize a disk for CVM, log on to the master node, then use the vxdiskadm program to
initialize multiple disks, or use the vxdisksetup command to initialize one disk at a time, as
in the following example:
# /usr/lib/vxvm/bin/vxdisksetup -i /dev/dsk/c0t3d2
Creating Disk Groups for RAC
Use the vxdg command to create disk groups. Use the -s option to specify shared mode, as in
the following example:
# vxdg -s init ops_dg c0t3d2
Verify the configuration with the following command:
# vxdg list
NAME STATE ID
rootdg enabled 971995699.1025.node1
ops_dg enabled,shared 972078742.1084.node2
Creating Volumes
Use the vxassist command to create logical volumes. For example:
# vxassist -g log_files make ops_dg 1024m
This command creates a 1024 MB volume named log_files in a disk group named ops_dg.
The volume can be referenced with the block device file /dev/vx/dsk/ops_dg/log_files
or the raw (character) device file /dev/vx/rdsk/ops_dg/log_files.
Verify the configuration with the following command:
# vxdg list
IMPORTANT: After creating these files, use the vxedit command to change the ownership of
the raw volume files to oracle and the group membership to dba, and to change the permissions
to 660. Example:
# cd /dev/vx/rdsk/ops_dg
# vxedit -g ops_dg set user=oracle *
# vxedit -g ops_dg set group=dba *
# vxedit -g ops_dg set mode=660 *
The logical volumes are now available on the primary node, and the raw logical volume names
can now be used by the Oracle DBA.
Mirror Detachment Policies with CVM
The required CVM disk mirror detachment policy is ‘global’, which means that as soon as one
node cannot see a specific mirror copy (plex), all nodes cannot see it as well. The alternate policy
is ‘local’, which means that if one node cannot see a specific mirror copy, then CVM will deactivate
access to the volume for that node only.
Creating Volumes 101