TRAP/INFORM notification

pysnmp.hlapi.asyncore.sendNotification(snmpEngine, authData, transportTarget, contextData, notifyType, varBinds, cbFun=None, cbCtx=None, lookupMib=False)

Send SNMP notification.

Based on passed parameters, prepares SNMP TRAP or INFORM notification (RFC 1905#section-4.2.6) and schedules its transmission by I/O framework at a later point of time.

  • snmpEngine (SnmpEngine) – Class instance representing SNMP engine.
  • authData (CommunityData or UsmUserData) – Class instance representing SNMP credentials.
  • transportTarget (UdpTransportTarget or Udp6TransportTarget) – Class instance representing transport type along with SNMP peer address.
  • contextData (ContextData) – Class instance representing SNMP ContextEngineId and ContextName values.
  • notifyType (str) – Indicates type of notification to be sent. Recognized literal values are trap or inform.
  • varBinds (tuple) – Single NotificationType class instance representing a minimum sequence of MIB variables required for particular notification type. Alternatively, a sequence of ObjectType objects could be passed instead. In the latter case it is up to the user to ensure proper Notification PDU contents.
Other Parameters:
  • cbFun (callable) – user-supplied callable that is invoked to pass SNMP response to INFORM notification or error to user at a later point of time. The cbFun callable is never invoked for TRAP notifications.
  • cbCtx (object) – user-supplied object passing additional parameters to/from cbFun.
  • lookupMib (bool) – lookupMib - load MIB and resolve response MIB variables at the cost of slightly reduced performance. Default is True.


User-supplied cbFun callable must have the following call signature:

  • snmpEngine (SnmpEngine): Class instance representing SNMP engine.
  • sendRequestHandle (int): Unique request identifier. Can be used for matching multiple ongoing INFORM notifications with received responses.
  • errorIndication (str): True value indicates SNMP engine error.
  • errorStatus (str): True value indicates SNMP PDU error.
  • errorIndex (int): Non-zero value refers to varBinds[errorIndex-1]
  • varBinds (tuple): A sequence of ObjectType class instances representing MIB variables returned in SNMP response in exactly the same order as varBinds in request.
  • cbCtx : Original user-supplied object.
Returns:sendRequestHandle (int) – Unique request identifier. Can be used for matching received responses with ongoing INFORM requests. Returns None for TRAP notifications.
Raises:PySnmpError – Or its derivative indicating that an error occurred while performing SNMP operation.


>>> from pysnmp.hlapi.asyncore import *
>>> snmpEngine = SnmpEngine()
>>> sendNotification(
...     snmpEngine,
...     CommunityData('public'),
...     UdpTransportTarget(('', 162)),
...     ContextData(),
...     'trap',
...     NotificationType(ObjectIdentity('SNMPv2-MIB', 'coldStart')),
... )
>>> snmpEngine.transportDispatcher.runDispatcher()