Using Serviceguard Extension for RAC, 6th Edition, April 2008

NOTE: To reduce the risk of failure of multiple subnets simultaneously, each

subnet must have its own networking infrastructure (including networking

switches).

• A double switch failure resulting in the simultaneous failure of CSS-HB subnet

and RAC-IC network on all nodes may result in loss of services (Assuming the

CSS-HB subnet is different from RAC-IC network). The failure handling of

interconnect subnets might choose to retain one node for CSS-HB subnet failures

and to retain RAC instance on some other node for RAC-IC subnet failures.

Eventually, the database instance will not run on any node as the database instance

is dependent on clusterware to run on that node.

Cluster Interconnect Monitoring Restrictions

In addition to the above limitations the Cluster Interconnect Monitoring feature has

the following restrictions:

• Cluster Lock device/Quorum Server/Lock Lun must be configured in the cluster.

• CLUSTER_INTERCONNECT_SUBNET can be used to monitor only IPv4 subnets.

• To change default Serviceguard cluster configuration parameter NODE_TIMEOUT,

HEARTBEAT_INTERVAL or Oracle Clusterware configuration parameter CSS

misscount, set Oracle misscount to the higher of:

— 195 seconds

— 40*SG_NODE_TIMEOUT + 25 * SG_HB_INTERVAL + 120 seconds

Creating a Storage Infrastructure with LVM

In addition to configuring the cluster, you create the appropriate logical volume

infrastructure to provide access to data from different nodes. This is done with Logical

Volume Manager (LVM), Veritas Cluster Volume Manager (CVM), or Veritas Volume

Manager (VxVM). LVM and VxVM configuration are done before cluster configuration,

and CVM configuration is done after cluster configuration.

This section describes how to create LVM volume groups for use with Oracle data.

Before configuring the cluster, you create the appropriate logical volume infrastructure

to provide access to data from different nodes. This is done withvgfj Logical Volume

Manager. Separate procedures are given for the following:

• Building Volume Groups for RAC on Mirrored Disks

• Building Mirrored Logical Volumes for RAC with LVM Commands

• Creating RAC Volume Groups on Disk Arrays

• Creating Logical Volumes for RAC on Disk Arrays

Creating a Storage Infrastructure with LVM 55