Data Replication

Data replication enables the Sun Cluster Geographic Edition software to mirror data from one system to another system. The Sun Cluster Geographic Edition software supports Sun StorEdge Availability Suite 3.2.1 software and Hitachi TrueCopy software for data repliation.

The Sun StorEdge Availability Suite 3.2.1 software is a host-based replication facility that replicates disk volumes between geographically separated primary clusters and secondary clusters in real time. Remote mirror replication enables data from the master volume of the primary cluster to be replicated to the master volume of the geographically separated secondary cluster through a TCP/IP connection. A remote mirror bitmap tracks differences between the master volume on the primary disk and the master volume on the secondary disk.

The remote mirror software continually replicates the data to remote sites while your applications are accessing the data volumes. You can also manually update the data on the secondary site volume by issuing a command to synchronize the primary and secondary site volumes. You can also restore data from the secondary volume to the primary volume by issuing a command to reverse-synchronize the volumes. For more information about the Sun StorEdge Availability Suite 3.2.1 software, see the product documentation.

The Hitachi TrueCopy software is a storage-based replication facility that provides a host-independent data replication for geographically separated clusters. Hitachi TrueCopy software enables the primary volumes to remain online for all hosts and while processing both read and write I/O operations. If a disaster or system failure occurs, the secondary copy of the data can be run for a recovery with little loss of data. For more information about the Hitachi TrueCopy software, see the product documentation.

Resource groups and device groups enable the Sun Cluster Geographic Edition software to manage data replication and takeover between clusters. You can also configure a protection group to replicate data from a primary cluster to a secondary cluster. For more information about configuring data replication, see Chapter 7, Replicating Data With Hitachi TrueCopy Software, in Sun Cluster Geographic Edition System Administration Guide.

Replication Resource Groups

The Sun Cluster Geographic Edition software extends Sun Cluster resource management features to integrate the data replication products. When you configure a protection group, the Sun Cluster Geographic Edition software creates replication resource groups for monitoring and controlling data replication.

Disk Device Groups

A disk device group is a hardware resource that Sun Cluster manages. A disk device group is a type of global device that the Sun Cluster software uses to register volume manager disk groups. The Sun Cluster Geographic Edition software configures Sun Cluster disk device groups to include replication. For information about configuring disk device groups in Sun Cluster, refer to Chapter 7, Replicating Data With Hitachi TrueCopy Software, in Sun Cluster Geographic Edition System Administration Guide.