Background: Know: SEQUENCE, OID , enterprise part of OID tree, TimeTicks, varBindList, Prerequisites - network address, Recognize:

Anticipates: agent-addr xxLP

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Trap information

Generic Traps

SNMPv1-Trap message formatEdit

The SNMPv1-Trap message, which is also called SNMPv1 Trap PDU format, consists of enterprise, agent-addr, generic-trap, specific-trap, time-stamp and variable-bindings. The whole SNMPv1-Trap message format is defined in RFC1157, and it is shown in figure 1.</p>

Figure 1: the SNMPv1-Trap message format.

Explanations are given as follows.

Field NameSyntaxSize(bytes)Description
enterpriseSequence of IntegerVariableThis field is an object identifier for a group. It is used to indicate the type of object that generates the trap.
agent-addrNetworkAddress4It provides the network address of the managed object that generates the trap. And it can be used to specify the preferred address in case of multihomed host.
generic-trapInteger4The generic-trap is used to indicate one of predefined-generic trap types. Its value is a number of 4 bypes long.
specific-trapInteger4The generic-trap is used to specify an implementation-specific trap types. Its value is a number of 4 bypes long.
time-stampTimeTicks4The value of time-stamp indicates the amount of time between the generation of the trap and the element which sends the Trap PDU message last rebooted.
variable-bindingsVariableVariableThis field consists of a set of name-value pairs. Each pair binds associates a particular object instance with its current value.

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