Event Management › Implementation Process › SNMP Facilities › SNMP Traps

SNMP Traps

An SNMP trap is, typically, an unsolicited message that reports on one of two types of events:

• Extraordinary events indicating that something is wrong or an error has occurred
• Confirmed events providing information about status, such as a process ending normally or a printer coming online

A variety of SNMP agents are available, including those provided through Agent Technology. They vary greatly in purpose, complexity, and implementation.

Despite their differences, all SNMP agents have the ability to:

• Respond to SNMP queries
• Issue an SNMP trap
• Accept instructions about where to route SNMP traps

Accepting instructions on where to route SNMP traps is typically referred to as accepting a setting for a trap destination. Setting the trap destination is important because traps should be directed to where they can be acted on.

Recognizing this, many vendors provide facilities for setting a system‑wide default trap destination through an SNMP configuration file. For example, some UNIX platforms set their trap destination in the file /etc/snmpd.conf. This path and file name may be different for your system.

Accepting a trap destination setting, however, is only half the job. There also must be something at that trap destination that can receive and process that trap. Enterprise Management provides an agent called the CA trap daemon, catrapd, which can receive and process any traps directed to the destination (computer) where it is executing.

Any SNMP trap that catrapd receives is unpacked (decoded) and sent to the other Event Management components for processing. As part of this decoding, character representations, or strings, can be assigned to substitute names for the enterprise IDs that are part of the SNMP trap. CA Common Services for z/OS provides the following translation files for that purpose:

$CAIGLBL0000/snmp/dat/enterprise.dat

The file is self‑documenting. You can add additional entries to this file by using a text editor.

Note: For more information about catrapd and SNMP usage, see the Reference Guide.