Sun Microsystems Virtual Tape Library manual Auto Replication

Key VTL features and options

Auto Replication

The Auto Replication option copies virtual tapes from a virtual library to another VTL server whenever a backup application or utility moves a virtual tape to an import/export slot.

You enable Auto Replication at the library level when you create a virtual tape library (see “Setting up the Auto Replication option” on page 50). You can then selectively enable the feature on a tape‐by‐tape basis as tapes are created. You cannot alter the Auto Replication status of an existing virtual tape.

Replication

The VTL Replication feature maintains synchronized replica resource copies of virtual tapes on a designated VTL server. At the end of a policy‐defined replication interval, VTL software copies data that has changed and is not currently in use from the primary virtual tapes to the replica resources.

During normal operation, backup clients have no access to replica resources—the latter are purely internal protections within the VTL system. If the primary virtual tape is corrupt or otherwise unusable, however, administrators can promote replica resources as part of their disaster recovery process. Once promoted, the replica resource becomes the primary virtual tape, with the same barcode and attributes. Backup clients can thus use it for recovery as if it were, in fact, the original copy.

You can configure the VTL Replication feature for either:

■Remote Replication or

■Local Replication.

Remote Replication

Remote Replication maintains synchronized copies of virtual tape volumes on the storage arrays of a pair of VTL appliances that are connected across Ethernet local area networks (LANs) or Wide Area Networks (WANs). Data is thus transferred at LAN/WAN speed, but is not subject to the distance limitation imposed by Fibre Channel storage area network (SAN) technology.

Local Replication

Local Replication maintains local, synchronized copies of virtual tape volumes on the storage arrays of a single VTL appliance. Data is transferred at SAN speed over distances limited to the maximum possible with a Fibre Channel SAN.

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