GETNEXT command

pysnmp.hlapi.twisted.nextCmd(snmpEngine, authData, transportTarget, contextData, *varBinds, **options)

Performs SNMP GETNEXT query.

Based on passed parameters, prepares SNMP GETNEXT packet (RFC 1905#section-4.2.2) and schedules its transmission by twisted I/O framework at a later point of time.

Parameters:
  • 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.
  • *varBinds (ObjectType) – One or more class instances representing MIB variables to place into SNMP request.
Other Parameters:
 

**options – Request options:

  • lookupMib - load MIB and resolve response MIB variables at the cost of slightly reduced performance. Default is True.
Returns:

deferred (Deferred) – Twisted Deferred object representing work-in-progress. User is expected to attach his own success and error callback functions to the Deferred object though addCallbacks() method.

Raises:

PySnmpError – Or its derivative indicating that an error occurred while performing SNMP operation.

Notes

User success callback is called with the following tuple as its first argument:

  • errorStatus (str) : True value indicates SNMP PDU error.

  • errorIndex (int) : Non-zero value refers to varBinds[errorIndex-1]

  • varBinds (tuple) :

    A sequence of sequences (e.g. 2-D array) of ObjectType class instances representing a table of MIB variables returned in SNMP response. Inner sequences represent table rows and ordered exactly the same as varBinds in request. Response to GETNEXT always contain a single row.

User error callback is called with errorIndication object wrapped in Failure object.

Examples

>>> from twisted.internet.task import react
>>> from pysnmp.hlapi.twisted import *
>>>
>>> def success(args):
...     (errorStatus, errorIndex, varBindTable) = args
...     print(errorStatus, errorIndex, varBindTable)
...
>>> def failure(errorIndication):
...     print(errorIndication)
...
>>> def run(reactor):
...     d = nextCmd(SnmpEngine(),
...                 CommunityData('public'),
...                 UdpTransportTarget(('demo.snmplabs.com', 161)),
...                 ContextData(),
...                 ObjectType(ObjectIdentity('SNMPv2-MIB', 'system'))
...     d.addCallback(success).addErrback(failure)
...     return d
...
>>> react(run)
(0, 0, [[ObjectType(ObjectIdentity(ObjectName('1.3.6.1.2.1.1.1.0')), DisplayString('SunOS zeus.snmplabs.com 4.1.3_U1 1 sun4m'))]])
>>>