Architecture considerations and best practices for architecting an Oracle RAC solution with Serviceguard and SGeRAC

Since ASM supports only database data files and log files, the following storage management

methods are required for non-database files if ASM is used on HP-UX:

• A local file system or Cluster File System (CFS) for Oracle Clusterware binaries and configuration

files and RAC binaries and configuration files.

• Shared storage for Oracle Clusterware data: voting disk and OCR files. Prior to RAC 11gR2, this

storage has to be configured either as shared raw devices, shared raw volumes, or files in the CFS.

Oracle Clusterware needs to be up and running before the ASM daemon can start. Therefore, for

versions prior to 11gR2, ASM cannot be used for Oracle Clusterware data on HP-UX systems.

Starting with 11gR2, Oracle RAC supports voting disks and Clusterware data (OCR files) on

ASM storage.

CAUTION: There is no shared awareness of LUN use between ASM and LVM or VxVM. This means

that the system administrator must be careful not to accidentally allocate a LUN already allocated for

LVM or VxVM use to ASM use (or vice-versa). See the section

ASM over SLVM later in this document

for information on how to use ASM with SLVM to address this issue.

Architecting an Oracle RAC solution with SGeRAC

Since the release of Oracle 10g, HP has recommended a combined Oracle Clusterware and

SGeRAC configuration for RAC deployments on HP-UX. In this combined environment, the

responsibilities of SGeRAC include:

• Providing cluster membership information to the Oracle Clusterware CSS daemon

• Providing clustered storage to meet the needs of Oracle Clusterware and RAC database instances

– The Oracle Clusterware voting disk and OCR can be configured as shared raw logical volumes

(LVs) managed by SGeRAC using Shared Logical Volume Manager (SLVM), or Cluster Volume

Manager (CVM), or as shared files managed by SGeRAC using the CFS. The Oracle Clusterware

home directory, containing Oracle Clusterware executables, can also be stored in a CFS.

– The RAC database files can be configured as shared raw LVs managed by SGeRAC using SLVM

or CVM.

o Beginning with Oracle 10gR2 and SGeRAC A.11.17, the RAC database files may also be

configured as files in Oracle ASM Disk Groups. The members of the ASM Disk Groups are

recommended to be configured as shared raw LVs managed by SGeRAC using SLVM.

Beginning with SGeRAC A.11.17.01 (on HP-UX 11i v3), ASM disk groups are supported over

raw disks because 11i v3 Native Multipathing can be used.

o Beginning with SGeRAC A.11.17, the RAC database files may be configured as shared files

managed by SGeRAC using CFS. The Oracle database home directory, containing Oracle

database server executables, can also be stored in a CFS.

The responsibilities of Oracle Clusterware in this combined environment include:

• Management of the database and associated resources (database instances, services, VIPs,

• Management of Oracle ASM instances, if configured

listeners, etc.)

Previously, Oracle VIPs and Serviceguard RIPs could not be configured on the same subnet on the same node due to potential collisions during

IP address configuration. This issue has been addressed in Oracle 10.2.0.2 and later for the HP Integrity platform and is addressed in Oracle

10.2.0.3 and later for the HP 9000 platform.