The Master Agent enables the mapper to report traps to the agent by building a Master Agent trap PDU and sending it to the agent.
The trap is caused by an unsolicited message known as an INDICATION from the DMI SP. If these indications are from the component, they are called events. The mapper receives all indications after it has subscribed to the SP by adding an entry into its subscription table. The mapper also sets the filter conditions for receiving every type of event. Because the mapper is already waiting for requests from the agent, this routine is a separate thread. The subagent determines what OIDs are sent with the trap. The following list describes the different types of indications.
DmiDeliverEvent This indication is generated by the component. The SP passes it to all the MI applications having their valid entries in the subscription and filter tables maintained by the SP. The snmpXdmid mapper matches the OID prefix to the component ID, generating the event for building the TrapOID. The groupId and attributes are also part of the event. The snmpXdmid mapper uses all relevant information in the event (apart from the OID prefix itself) to generate the TrapOID. The snmpXdmid generates a SNMP-specific trap, with specific trapID=14.
DmiComponentAdded This indication is generated by the SP when a new component is registered. New components may be registered for existing .MAP files or for a totally new .MAP file. When this trap is received by snmpXdmid, it unregisters all the registered OIDs in the Master Agent, rereads all the .MAP files, and then goes through the process of reregistering all of the OIDs with the Master Agent. This helps to keep the subagent translation tables in sync with the .MAP files, especially since the .MAP files are generated external to the mapper. The mapper then generates an SNMP-specific trap with trapID = 7.
DmiComponent-Deleted This indication is generated by the SP when an existing component ID is unregistered with the SP. The snmpXdmid mapper modifies the translation tables upon receiving this indication. By default, it generates an SNMP trap with trapID=8.
DmiGroupAdded This indication is generated by SP when a new group is registered with it under a component ID. This results in the updating of translation tables in snmpXdmid. An SNMP trap is generated with trapID=11.
When the management application subscription for indication hits the warning timestamp. A flag indicates the warning aspect of the indication. An NMP trap with trapID=15 is generated.
When the management application subscription for indication hits the expiration timestamp. An SNMP trap with trapID=16 is generated.