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

Using Serviceguard primary and standby links is the preferred HA model to provide HA for the cluster

communications interconnect network HA. With redundancy through Serviceguard primary and

standby, Serviceguard monitors the network and performs local failover if the primary network

becomes unavailable.

General principles

It is preferred to have all interconnect traffic for cluster communications on a single heartbeat network

with a standby interface so that Serviceguard will monitor the network and resolve interconnect

failures by cluster reconfiguration. This preferred configuration is the recommended common

configuration.

The following examples are instances when it is not possible to place all interconnect traffic on the

same network:

• RAC GCS (cache fusion) traffic may be very high, so a separate network for RAC-DB-IC may

be needed

. One RAC-DB-IC may interfere with another RAC-DB-IC on the same cluster.

RAC-DB-IC may also interfere with heartbeat traffic.

• Some networks are not supported by CFS/CVM, so the RAC-DB-IC traffic may be on a

separate network.

• Certain configurations for fast re-configuration require at least SG heartbeat network, while

CSS-HB and and RAC-DB-IC does not support multiple network for HA purposes. Note:

Starting A.11.19, the faster failover capability is in the base Serviceguard product.

In these cases, you may see a longer time to recover some network failures beyond those protected by

primary and standby, unless special logic is developed.

Cluster Interconnect Configurations for SLVM

Configurations with SLVM have configurations that are combinations of SG-HB, CSS-HB and RAC-DB-

IC on Ethernet. The following figures show several examples on how cluster interconnect traffic can

be distributed. This is not an exhaustive list.

Figure 1. Preferred: SG-HB, CSS-HB, and RAC-DB-IC on same subnet

Figure 1 shows a common configuration where all inter-cluster traffic flows through the primary

network. This configuration is suitable for most common installations where the RAC traffic does not

saturate the network and negatively affect other components. There is one network and the network

See CLUSTER_INTERCONNECTS, page 5-11, Oracle Clusterware and Oracle Real Application Clusters Administration and Deployment Guide

version 10g Release 2 (10.2) (http://download-west.oracle.com/docs/cd/B19306_01/rac.102/b14197.pdf )

Node A

LAN 1

LAN

Node B

LAN 1

LAN 2

CSS-HB

RAC

Private

(standby)

Private

(primary)