Overview of Traps

The optional Remote Monitoring feature provides the capability for the LSMS to report certain events and alarms to a remote location, using the industry-standard Simple Network Management Protocol (SNMP). The LSMS implements an SNMP agent.

Customers can use this feature to cause the LSMS to report events and alarms to another location, which implements an SNMP Network Management System (NMS). An NMS is typically a standalone device, such as a workstation, which serves as an interface through which a human network manager can monitor and control the network. The NMS typically has a set of management applications (for example, data analysis and fault recovery applications).

For more information about the LSMS implementation of an SNMP agent, see “Understanding the SNMP Agent Process”.

SNMP Version 3 Trap PDU Format

An SNMPv3 trap PDU consists of the following fields:

PDU Type
Specifies the type of PDU (in this case, trap).
Request ID
Used to associate requests with responses.
Error Status
Specifies an error or error type in response PDUs only (else set to 0)
Error Index
Associates an error with a particular object instance in response PDUs only (else set to 0)
Variable Bindings
Each variable binding contains an object field followed by its value field. The object and value fields together specify information about the event being reported.

SNMP Version 1 Trap PDU Format

An SNMPv1 trap PDU consists of the following fields:

PDU Type field, which specifies the type of PDU (in this case, trap).
Enterprise field, which identifies the device generating the message. For the LSMS SNMP agent, this field is 323.
Agent address field, which contains the IP address of the host that runs SNMP agent. For the LSMS SNMP agent, this field contains the IP address of the LSMS active server.
Generic trap type, which can be set to any value from 0 through 6. Currently, the LSMS supports only the value 6, which corresponds to the enterpriseSpecific type of trap request.
Specific trap type, which can be used to identify a specific trap.
Time stamp, which indicates how many hundredths of a second have elapsed since the last reinitialization of the host that runs the SNMP agent.
One or more variables bindings, each of which contains an object field followed by a value field. The object and value fields together specify information about the event being reported.