Options for recovery operations after conditional restart

The recovery operations that take place during restart are controlled by the currently active conditional restart control record. An active control record is created or deactivated by running the change log inventory utility with the CRESTART control statement.

You can choose to:

• Retain a specific portion of the log for future Db2 processing
• Read the log forward to recover indoubt and uncommitted units of recovery
• Read the log backward to back out uncommitted and in-abort units of recovery
• Do a cold start, not processing any log records

A conditional restart record that specifies left truncation of the log causes any postponed-abort units of recovery that began earlier than the truncation RBA to end without resolution. The combination of unresolved postponed-abort units of recovery can cause more records than requested by the BACKODUR system parameter to be processed. The left truncation RBA takes precedence over BACKODUR in this case.

Be careful about doing a conditional restart that discards log records. If the discarded log records contain information from an image copy of the Db2 directory, a future execution of the RECOVER utility on the directory fails.