librenms-librenms/doc/Developing/SNMP-Traps.md

source: Developing/SNMP-Traps.md

Creating snmp trap handlers

Create a new class in LibreNMS\Snmptrap\Handlers that implements the LibreNMS\Interfaces\SnmptrapHandler interface.

Register the mapping in the config/snmptraps.php file. Make sure to use the full trap oid.

'IF-MIB::linkUp' => \LibreNMS\Snmptrap\Handlers\LinkUp::class

The handle function inside your new class will receive a LibreNMS/Snmptrap/Trap object containing the parsed trap. It is common to update the database and create event log entries within the handle function.

Getting information from the Trap

Source information

$trap->getDevice();   // gets Device model for the device associated with this trap
$trap->getHostname(); // gets hostname sent with the trap
$trap->getIp();       // gets source IP of this trap
$trap->getTrapOid();  // returns the string you registered your class with

Retrieving data from the Trap

$trap->getOidData('IF-MIB::ifDescr.114');

getOidData() requires the full name including any additional index. You can use these functions to search the oid keys.

$trap->findOid('ifDescr');  // returns the first oid key that contains the string
$trap->findOids('ifDescr'); // returns all oid keys containing the string

Advanced

If the above isn't adequate, you can get the entire trap text

$trap->getRaw();