Processing INGREQ, INGMOVE and INGGROUP Commands

The INGREQ, INGMOVE, and INGGROUP commands use the FDBK parameter that causes the final result of the command execution to be reported back to the requested destination. It thus makes the these commands quasi-synchronous.

Processing for INGMOVE differs in that it initiates the move operation, but does not wait for the completion of the move operation.

Processing of an INGREQ command is slightly different because, by definition, the INGREQ command works asynchronously.

Invoking the INGREQ command causes a start or stop vote to be placed against the resources that are specified in the command. This does not necessarily mean that the resource is immediately started or stopped: It depends on the presence of other, higher priority votes (that may request the opposite) or whether all dependencies are fulfilled.

After informing the automation manager about the new request, the INGREQ command checks whether the specified resource is already in the desired state. If so, it posts the operation complete. Otherwise, it subscribes a status observer for the specified resource and sets up a timer. If the timer expires and resource is not in the requested state, INGREQ sets the operation status in error. It calls the EQQUSINT service, which passes the completion code to the TWS tracker on the local system.