Sample Configurations with SGeRAC and Oracle RAC 10gR2, March 2009

Storage

Oracle Clusterware (OC) assumes the required storage is available when OC starts. Therefore, OC

does not perform any storage activation and leaves it up to the platform or users to activate the

storage prior to starting OC. For SGeRAC configurations, Serviceguard packages are used as the

mechanism to activate storage prior to starting OC. For SLVM and CVM configurations, the shared

storage activation is performed by the Serviceguard package that starts OC. For CFS configurations,

the shared storage activation is performed by multi-node packages; therefore, the Serviceguard

package that starts OC must have a dependency on the relevant multi-node packages.

Oracle Clusterware requirements: OCR and voting disk

Oracle Cluster Registry (OCR)

The OCR requires 100 MB of disk space. The OCR must be shared and accessible by all cluster

nodes. OC uses the OCR to keep Oracle cluster information and configuration information regarding

cluster databases. It is also used to keep track of processes that the Oracle Clusterware controls.

Voting disk

The voting disk requires 20 MB of disk space. As with the OCR, the voting disks is shared and

accessible by all cluster nodes. Oracle uses the voting disk to manage Oracle cluster software

membership. The voting disk is used as a health check device; case of network failure; it is used to

arbitrate cluster ownership among the instances.

Shared storage

Each OCR and voting disk can exist as follows:

• SLVM – The file can reside on SLVM as a raw logical volume where the whole logical volume

is used as the vote disk. In this case, the vote disk is the raw logical volume.

• CFS – The file can reside on a cluster file system as a regular file. In this case, it is not really

a disk in the traditional sense of a physical device.

• CVM – The file can reside on CVM as a raw volume similar to SLVM raw logical volume.

Note:

Oracle uses the term voting disk. Sometimes, the vote disk is also referred

as the voting disk. It is supported to place the OCR and voting disk on

SLVM, CFS, or CVM. The advantages include multi-path support,

mirroring, and controlled access.

RAC instance data files

With SGeRAC, RAC instance data files may reside on SLVM or CVM raw volumes, CFS, and ASM

over SLVM, ASM over raw disks, and raw disks.

Oracle binaries (Clusterware and RAC)

Oracle binaries must reside on either local file system or cluster file system (CFS).

Archive log files

Oracle archive log files may be needed for database recovery and should be available to the node

that performs database recovery. The archive logs may reside on cluster file system (CFS), or a file