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

Serviceguard Configuration for Oracle 10g RAC
Creating Volumes
Chapter 2 107
Creating Volumes
Use the vxassist command to create logical volumes. The following is
an example:
# vxassist -g ops_dg make log_files 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.
This policy can be re-set on a disk group basis by using the vxedit
command, as follows:
# vxedit set diskdetpolicy=global <DiskGroupName>