Best Practices for SGeRAC and Oracle RAC on HP-UX 11i, March 2009

Client failover is needed when failures affect existing and new client sessions. These failures include

node failures (e.g. power failures) and network failures (e.g. all redundant network interface or links

failed). Protection is available at three levels:

1. Oracle Fast Application Notification (FAN)

2. Remote virtual IP address (VIP) fail over

3. Client connect timeout

Clients that are FAN integrated or using the FAN API may interrupt existing sessions and failover.

Remote VIP failover is useful for non-FAN clients attempting to connect to the local node to avoid the

TCP connect timeout. The client connect timeout is useful when client connect takes a long time for

whatever reason.

VIP high availability

This section describes high availability for VIP.

Previously, Oracle virtual IP address (VIP) and Serviceguard relocatable IP address (RIP) should not

exist on the same subnet on the same because of potential collisions on IP address configuration.

Note:

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.

Serviceguard local LAN failover – preferred choice

For client public network HA in a SGeRAC configuration, the preferred method for network HA is to

use Serviceguard primary and standby interfaces. Serviceguard monitors the redundant network and

additional APA software is not required.

When the client network is configured with Serviceguard local LAN failover, Serviceguard performs

the local LAN failover and Oracle Clusterware (OC) configures the VIP after Serviceguard local LAN

failover. Since OC performs monitoring and manages the VIP address, client connectivity maybe

unavailable until OC detects the outage and configures the VIP address on the local node.

Local LAN failover using APA

When APA is used to bond the network interface cards, APA provides traffic distribution and load

balancing capability among multiple physical network interface cards (NIC) or links. Load balancing

may be useful in configurations where a single interface is insufficient to handle the network traffic.

When a physical NIC or link fails, APA provides HA by distributing traffic among the remaining NIC

or links. One virtual link is presented to OC and APA network load balancing is transparent to OC.

APA requires that all the NICs in the link aggregate be of the same type. Since APA network

connections go to the same switch, a switch failure causes outage of the client network.

When APA/Hot Standby is used, APA/Hot Standby provides the primary-to-hot-standby failover by

rerouting traffic from failed primary link to hot standby link. APA/Hot Standby does not load

balance. Serviceguard does not monitor this network. One virtual network link is presented to OC

and the physical failover is transparent to OC since the same virtual network link remains available.

Both NICs must be the same type as with other types of APA.

See Doc ID: Note:296874.1 Configuring the HP-UX Operating System for the Oracle 10g VIP at https://metalink.oracle.com/ (Oracle

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