25.18.5 Notes on using the rapid system switchover facility

Organization of this subsection
(1) Actions requiring restarting HiRDB (or unit) in the standby system
(2) RDAREA opening trigger attributes
(3) Linking with OLTP products

(1) Actions requiring restarting HiRDB (or unit) in the standby system

After taking one of the actions listed below, terminate then restart HiRDB on the standby system (unit in the standby system in the case of a HiRDB/Parallel Server). If HiRDB on the standby system is not restarted, it will terminate abnormally when a system switchover occurs.

If HiRDB in the standby system terminated abnormally, use the pdstart command (pdstart -u or pdstart -q for HiRDB in the standby system) to start HiRDB in the standby system.

(2) RDAREA opening trigger attributes

Units in the standby system that are subject to the rapid system switchover facility do not open any RDAREAs when in waiting status. To minimize the time required for system switchover, the rapid system switchover facility opens only the RDAREAs needed for full recovery when a system switchover occurs. Therefore, the RDAREA opening trigger attribute of the standby system does not become INITIAL. The RDAREAs with the INITIAL attribute change to DEFER.

For details about RDAREA open attributes, see 15.5 Modifying an RDAREA opening trigger attribute (RDAREA modification).

(3) Linking with OLTP products

Caution is urged when all of the conditions listed below are present:

In such a case, if the OLTP products perform recovery processing on an undetermined transaction, the X/Open-compliant API may return an error and not be able to recover the transaction. If this problem occurs, upgrade the HiRDB client to version 06-02-/B or later. If you cannot immediately upgrade the HiRDB client because, for example, you do not wish to stop the current job task, switch the HiRDB (unit) in the primary system from the standby system to the running system. However, this is only a temporary measure. Be sure to upgrade the HiRDB client after the current job task has been completed.