"""
Custom PySNMP MIBs location
+++++++++++++++++++++++++++

Send a series of SNMP GETBULK requests using the following options:

* with SNMPv3, user 'usr-none-none', no authentication, no privacy
* over IPv4/UDP
* to an Agent at demo.snmplabs.com:161
* for all OIDs within TCP-MIB::tcpConnTable column
* TCP-MIB Python module will be searched by a user-specified filesystem
  path (/opt/mib/pysnmp) and in Python package (python_packaged_mibs)
  which should be in sys.path

Functionally similar to:

| $ snmpbulkwalk -v3 -lnoAuthNoPriv -u usr-none-none -Cn0 -Cr50 \
|                demo.snmplabs.com  TCP-MIB::tcpConnTable

"""#
from pysnmp.hlapi import *

for errorIndication, \
    errorStatus, errorIndex, \
    varBinds in bulkCmd(SnmpEngine(),
                        UsmUserData('usr-none-none'),
                        UdpTransportTarget(('demo.snmplabs.com', 161)),
                        ContextData(),
                        0, 50,
                        ObjectType(ObjectIdentity('TCP-MIB', 'tcpConnTable').addMibSource('/opt/mibs/pysnmp').addMibSource('python_packaged_mibs')),
                        lexicographicMode=False):

    if errorIndication:
        print(errorIndication)
        break
    elif errorStatus:
        print('%s at %s' % (
                errorStatus.prettyPrint(),
                errorIndex and varBinds[int(errorIndex)-1][0] or '?'
            )
        )
        break
    else:
        for varBind in varBinds:
            print(' = '.join([ x.prettyPrint() for x in varBind ]))