How the Data Replication Subsystem Validates the Device Group

Before creating the protection group, the data replication layer validates that the horcmd daemon is running.

The data replication layer validates that the horcmd daemon is running on at least one of the nodes given in the Nodelist property. For more information about the horcmd daemon, see the Sun StorEdge SE 9900 V Series Command and Control Interface User and Reference Guide.

If the Cluster_dgs property is specified, then the data replication layer verifies that the device group specified is a valid Sun Cluster device group. The data replication layer also verifies that the device group is of a valid type.

The device groups specified in the Cluster_dgs property must be written to only by applications that belong to the protection group. This property must not specify device groups that receive information from applications outside of the protection group.

A Sun Cluster resource group is automatically created when the protection group is created.

This resource in this resource group monitors data replication. The name of the Hitachi TrueCopy data replication resource group is rg-tc-protection-group-name.

These automatically created replication resource groups are for Sun Cluster Geographic Edition internal implementation purposes only. Use caution when you modify these resource groups by using Sun Cluster commands.