Configuring Off-Host Processing

Off-host processing allows you to implement the following activities:

• Data Backup---As the requirement for 24 x 7 availability becomes essential for many businesses, organizations cannot afford the downtime involved in backing up critical data offline. By taking a snapshot of the data, and backing up from this snapshot, business-critical applications can continue to run without extended down time or impacted performance.
• Decision Support Analysis and Reporting---Because snapshots hold a point-in-time copy of a production database, a replica of the database can be set up using the snapshots. Operations such as decision support analysis and business reporting do not require access to up-to-the-minute information. This means that they can use a database copy that is running on a host other than the primary. When required, the database copy can quickly be synchronized with the data in the primary database.
• Testing and Training---Development or service groups can use snapshots as test data for new applications. Snapshot data provides developers, system testers and QA groups with a realistic basis for testing the robustness, integrity and performance of new applications.
• Database Error Recovery---Logic errors caused by an administrator or an application program can compromise the integrity of a database. By restoring the database table files from a snapshot copy, the database can be recovered more quickly than by full restoration from tape or other backup media.

Off-host processing is made possible by using the FastResync and disk group move, split and join features of VxVM. These features are described in the following sections.

You can also use such solutions in conjunction with the cluster functionality of VxVM.For implementation guidelines, see Implementing Off-Host Processing Solutions.