Data to mirror

Ideally, you must mirror all of your data. If disk space is an issue, however, you might not be able to do so. In this case, select certain critical chunks to mirror.

Critical chunks always include the chunks that are part of the root dbspace, the chunk that stores the logical-log files, and the chunk that stores the physical logs. If any one of these critical chunks fail, the database server goes offline immediately.

If some chunks hold data that is critical to your business, give these chunks high priority for mirroring.

Also give priority for mirroring to chunks that store frequently used data. This action ensures that the activities of many users would not be halted if one widely used chunk goes down.