HP Serviceguard Extension for RAC (SGeRAC) manual Configuring Packages for Oracle RAC Instances

Models: Serviceguard Extension for RAC (SGeRAC)

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For example, when a multi-node package (pkgA) is configured to run on all nodes of the cluster, and configured to monitor a subnet (SubnetA) using the CLUSTER_INTERCONNECT_SUBNET parameter:

If more than one instance of pkgA is running in the cluster and SubnetA fails on one of the nodes where the instance of pkgA is running, the failure is handled by halting the instance of pkgA on the node where the subnet has failed.

If pkgA is running on only one node of the cluster and SubnetA fails on that node, pkgA will continue to run on that node after the failure.

If pkgA runs on all nodes of the cluster and SubnetA fails on all nodes of the cluster, the failure is handled by halting all but one instance of pkgA. Where the instance of pkgA will be left running is randomly determined.

The following describes the behavior of cluster interconnect subnet monitoring feature under the following scenarios:

For a multi-node package with CLUSTER_INTERCONNECT_SUBNET configured, upon an explicit request to start the package on a node, no attempt to start the package instance on that node will be made if the subnet is not up on that node.

If a multi-node package with CLUSTER_INTERCONNECT_SUBNET configured is running on only one node of the cluster, with the subnet that it monitors is down on all nodes of the cluster, the restoration of the subnet on any other node does not affect the running instance. No attempt will be made automatically to start the package instance on the restored node. An attempt to start the instance of the package on the restored node will be made, if the user explicitly tries to start the package instance.

If a multi-node package with CLUSTER_INTERCONNECT_SUBNET is running on more than one node of the cluster, upon a failure of the subnet on all nodes where the package is running, all but one package instance will be halted one by one. Additionally, if NODE_FAIL_FAST_ENABLED is set to “YES” for such a package, all but one node will be brought down one by one. For example, one node will be brought down, cluster reformation will happen, another node will be brought down, and cluster reformation will happen until one node remains in the cluster.

NOTE: The CLUSTER_INTERCONNECT_SUBNET parameter is available only for use with multi-node packages.

For more information on the Cluster Interconnect Subnet Monitoring feature, refer to chapter 2, section “Cluster Communication Network Monitoring” (page 35). This section describes various network configurations for cluster communications in SGeRAC/10g or 11gR1/11gR2 RAC cluster, and how the package configuration parameter CLUSTER_INTERCONNECT_SUBNET can be used to recover from Oracle Cluster Communications network failures.

Configuring Packages for Oracle RAC Instances

Oracle instances can be configured as packages with a single node in their node list.

NOTE: Packages that start and halt Oracle instances (called instance packages) do not fail over from one node to another, they are single-node packages. You should include only one NODE_NAME in the package ASCII configuration file. The AUTO_RUN setting in the package configuration file will determine whether the RAC instance will start up as the node joins the cluster. Your cluster may include RAC and non-RAC packages in the same cluster.

Configuring Packages for Oracle Listeners

Oracle listeners can be configured as packages within the cluster (called listener packages). Each node with a RAC instance can be configured with a listener package. Listener packages are

18 Introduction to Serviceguard Extension for RAC

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HP Serviceguard Extension for RAC (SGeRAC) manual Configuring Packages for Oracle RAC Instances