The recovery process performs recovery in the event of a server or system failure. The recovery process maintains a history of important actions in its own message log file, iircp.log.

Each installation has a dmfrcp (data manipulation facility recovery process) that is assigned recovery responsibilities. In normal circumstances, transaction commit and rollback processing are handled within each DBMS server. In the event of a server or system failure, however, the recovery process performs the required recovery, including backing out uncommitted transactions and ensuring that committed transactions are properly reflected on disk.

The recovery process operates in the following modes:

Online recovery is performed when a server stops abnormally. In this case, users connected to other servers are generally unaffected by the recovery.

Offline recovery is performed when the installation is brought back up after it has stopped abnormally. In this case, the installation remains unavailable until the recovery process completes all required recovery.