Point-In-Time Copy Solutions

This chapter introduces the point-in-time copy solutions that you can implement using the VERITAS FlashSnap^TM technology.

VERITAS FlashSnap offers a flexible and efficient means of managing business critical data. It allows you to capture an online image of actively changing data at a given instant: a point-in-time copy. You can perform system backup, upgrade and other maintenance tasks on point-in-time copies while providing continuous availability of your critical data. If required, you can offload processing of the point-in-time copies onto another host to avoid contention for system resources on your production server.

Two kinds of point-in-time copy solution are supported by the FlashSnap license:

• Volume-level solutions are made possible by the Persistent FastResync and Disk Group Split/Join features of VERITAS Volume Manager. These features are suitable for implementing solutions where the I/O performance of the production server is critical.

The Persistent FastResync and Disk Group Split/Join features are described in Persistent FastResync of Volume Snapshots and Disk Group Split/Join.

• File system-level solutions use the Storage Checkpoint feature of VERITAS File System. Storage Checkpoints are suitable for implementing solutions where storage space is critical for:
• File systems that contain a small number of mostly large files.
• Application workloads that change a relatively small proportion of file system data blocks (for example, web server content and some databases).
• Applications where multiple writable copies of a file system are required for testing or versioning.

The Storage Checkpoints feature is described in Storage Checkpoints.

The FlashSnap license also supports the VERITAS FlashSnap Agent for Symmetrix. This feature is described in VERITAS FlashSnap Agent for Symmetrix.