HP Serviceguard Extension for RAC (SGeRAC) manual Creating a Storage Infrastructure with LVM

NOTE:

1.The “F” represents the Serviceguard failover time as given by the

max_reformation_duration field of cmviewcl –v –f line output.

2.SLVM timeout is documented in the whitepaper, LVM link and Node Failure Recovery Time.

Limitations of Cluster Communication Network Monitor

In Oracle Grid Infrastructure 11.2.0.2, using HAIP feature, Oracle allows to use a subnet for Oracle Clusterware (CSS-HB) and RAC interconnect (RAC-IC) communication which is not configured in SGeRAC cluster. So beginning with Oracle Grid Infrastructure 11.2.0.2 version, CLUSTER_INTERCONNECT_SUBNET parameter must not be used in SGeRAC A.11.20 toolkit Oracle Clusterware Multi-node and Oracle RAC database Multi-node packages.

CLUSTER_INTERCONNECT_SUBNET requires the subnet to be configured within the SGeRAC cluster.

The Cluster Interconnect Monitoring feature does not coordinate with any feature handling subnet failures (including self). The failure handling of multiple subnet failures may result in a loss of services, for example:

•A double switch failure resulting in the simultaneous failure of CSS-HB subnet and SG-HB subnet on all nodes of a two-node cluster. (Assuming the CSS-HB subnet is different from SG-HB subnet). Serviceguard may choose to retain one node while the failure handling of interconnect subnets might choose to retain the other node to handle CSS-HB network failure. As a result, both nodes will go down.

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 restriction:

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

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) or Veritas Cluster Volume Manager (CVM). LVM configuration is 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 with 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

40 Serviceguard Configuration for Oracle 10g, 11gR1, or 11gR2 RAC