There are two types of system-managed processes — system-managed rebuild and system-managed duplexing rebuild.

• System-managed rebuild, which is intended for use in planned reconfiguration scenarios, provides a means for rebuilding a structure with minimal participation from connectors to the structure. Connectors use the ALLOWAUTO parameter to indicate whether they support the system-managed rebuild process.
• System-managed duplexing rebuild, which is intended to provide a failure recovery capability, provides a means for duplexing the structure with minimal participation from connectors to the structure(s). The system allocates a duplexed instance of the structure, attaches connectors to the structure, copies data to the duplexed instance of the structure, and then maintains the structures in a synchronized state. In the event of a failure, such as a loss of connectivity, structure failure, or coupling facility failure affecting one of the two duplexed structure instances, the system can failover to the unaffected structure. Connectors use the ALLOWAUTO parameter to indicate whether they support the system-managed duplexing rebuild process.

In order to use the system-managed processes, an application must be written to handle the following:

• Processing of the Structure Temporarily Unavailable and Structure Available events.
• The use of extended restart tokens.
• Evaluation of the information presented with the Structure State Change event and reacting appropriately to changes in structure characteristics.
• The use of both physical structure version number to uniquely identify an instance of a structure. (In IXLYCONA, the physical version numbers are identified by CONAPHYSICALSTRUCTUREVERSION and CONAPHYSICALSTRUCTUREVERSION2; in IXLYEEPL, the physical version numbers are identified by EEPLSSCSTRPHYSICALVERSION and EEPLSSCSTRPHYSICALVERSION2.