Configuring Packages for Oracle RAC Instances

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 configured to automatically fail over from original node to an adoptive node. When the original node is restored, the listener package automatically fails back to the original node.

In the listener package ASCII configuration file, the FAILBACK_POLICY is set to AUTOMATIC. The SUBNET is set of monitored subnets. The package can be set to automatically startup with the AUTO_RUN setting.

Each RAC instance can be configured to register with listeners assigned to handle client connections. The listener package script is configured to add the package IP address and start the listener on the original node. Since each node can be configured with a listener package, when the listener package runs on an adoptive node, the package script should be configured to add the package IP address, but should not start the listener. If the adoptive node also has a RAC instance, the adoptive node should have its own listener package configured with its own package IP address and listener.

For example, on a two node cluster with one database, each node can have one RAC instance and one listener package. Oracle clients can be configured to connect to either package IP address (or corresponding hostname) using Oracle Net Services. When a node failure occurs, existing client connection to the package IP address will be reset after the listener package fails over and adds the package IP address. For subsequent connections, for clients configured with basic failover, clients would connect to the next available listener package's IP address and listener.