Data recovery after disk failures for distributed relational databases

Recovery is not possible for recently entered data if a disk failure occurs and all objects are not saved on tape or disk immediately before the failure. After previously saved objects are restored, the system is operational, but the database is not current.

Auxiliary storage pools (ASPs), checksum protection, and mirrored protection are IBM® i disk recovery functions that provide methods to recover recently entered data after a disk-related failure. These functions use additional system resources, but provide a high level of protection for systems in a distributed relational database. Because some systems might be more critical as servers than others, the distributed relational database administrator should review how these disk data protection methods can be best used by individual systems within the network.