Handling redundancy events

After binding to a TCAP user SAP, the application receives a TCAP_EVENT_RUN_STATE event indicating the redundancy state of the TCAP layer on the board. The event type associated with this event indicates one of the following states:

Event type

Description

TCAP_STANDALONE

Application is in a non-redundant configuration. Normal operation can begin.

TCAP_PRIMARY

TCAP task on this board is currently the primary board in a redundant board pair. Normal operation is allowed as long as the board remains the primary.

TCAP_BACKUP

TCAP task on this board is currently the backup board in a redundant board pair, monitoring the status of the primary. No active traffic passes through this SAP until the board becomes the primary member of the pair.

TCAP_BACKUP_READY

Backup task has finished updating its list of open transactions.


The TCAP_EVENT_RUN_STATE event is the first message posted to the application's queue for each SAP after the binding is confirmed. No data traffic (unitdata or connections requests) should be directed to this SAP until this event is received.

Refer to the SS7 Health Management Developer's Reference Manual for information on writing redundant TCAP applications.