13.6. SNMP Traps
As well as responding to SNMP requests like SET and GET, SNMP-enabled devices in the network can send out spontaneous notifications of local events. These notifications are sent either as SNMP traps or informs. Traps are datagrams sent without the expectation of a response. Informs are an improvement over traps because they expect a confirmation response and are re-sent when the trap receiver does not confirm them in a timely fashion. The time-out and the number of retries can be set by the trap sender as parameters to the snmptrap command.
13.6.1. Receiving Traps with snmptrapd
You can use snmptrapd to receive traps. In the 5.2.1 release of Net-SNMP, which we have been using in this chapter, all you have to do is open a separate ...