DB2® Universal Database for OS/390® Version 7.1 Certification Guide

Recovery Considerations

Recovery is a little different in the data sharing environment and there are several considerations necessary.

Each DB2 member writes to its own recovery logs and BSDSs, sort of a striping effect. Each DB2 member must be able to read the logs and BSDSs of every other member in the group so they must be on shared DASD with appropriate access granted. The reason it must be accessible is because the logs may be required from multiple DB2s to do media recovery. A group restart will require access to all logs (discussed a bit later).

The SCA contains information about all members' logs and BSDSs, and during the backward log recovery phase of DB2 startup, each member updates the SCA with new log information. It is then read ...