colinmcintosh / pysnmp

Pure-Python SNMP library

SNMP library for Python

This is a pure-Python, open source and free implementation of v1/v2c/v3 SNMP engine distributed under 2-clause BSD license.

The PySNMP project was initially sponsored by a PSF grant. Thank you!

Features

• Complete SNMPv1/v2c and SNMPv3 support
• SMI framework for resolving MIB information and implementing SMI Managed Objects
• Complete SNMP entity implementation
• USM Extended Security Options support (3DES, 192/256-bit AES encryption)
• Extensible network transports framework (UDP/IPv4, UDP/IPv6)
• Asynchronous socket-based IO API support
• Twisted, Asyncio and Trollius integration
• PySMI integration for dynamic MIB compilation
• Python eggs and py2exe friendly
• 100% Python, works with Python 2.4 though 3.6
• MT-safe (if SnmpEngine is thread-local)

Features, specific to SNMPv3 model include:

• USM authentication (MD5/SHA) and privacy (DES/AES) protocols (RFC3414)
• View-based access control to use with any SNMP model (RFC3415)
• Built-in SNMP proxy PDU converter for building multi-lingual SNMP entities (RFC2576)
• Remote SNMP engine configuration
• Optional SNMP engine discovery
• Shipped with standard SNMP applications (RC3413)

Download & Install

The PySNMP software is freely available for download from PyPI and GitHub.

Just run:

$ pip install pysnmp

to download and install PySNMP along with its dependencies:

• PyASN1
• PyCryptodome (required only if SNMPv3 encryption is in use)
• PySMI (required for MIB services only)

Besides the library, command-line SNMP utilities written in pure-Python could be installed via:

$ pip install pysnmp-apps

and used in the very similar manner as conventional Net-SNMP tools:

$ snmpget.py -v3 -l authPriv -u usr-md5-des -A authkey1 -X privkey1 demo.snmplabs.com sysDescr.0
SNMPv2-MIB::sysDescr.0 = STRING: Linux zeus 4.8.6.5-smp #2 SMP Sun Nov 13 14:58:11 CDT 2016 i686

Examples

PySNMP is designed in a layered fashion. Top-level and easiest to use API is known as hlapi. Here's a quick example on how to SNMP GET:

from pysnmp.hlapi import *

iterator = getCmd(SnmpEngine(),
                  CommunityData('public'),
                  UdpTransportTarget(('demo.snmplabs.com', 161)),
                  ContextData(),
                  ObjectType(ObjectIdentity('SNMPv2-MIB', 'sysDescr', 0)))

errorIndication, errorStatus, errorIndex, varBinds = next(iterator)

if errorIndication:  # SNMP engine errors
    print(errorIndication)
else:
    if errorStatus:  # SNMP agent errors
        print('%s at %s' % (errorStatus.prettyPrint(), varBinds[int(errorIndex)-1] if errorIndex else '?'))
    else:
        for varBind in varBinds:  # SNMP response contents
            print(' = '.join([x.prettyPrint() for x in varBind]))

This is how send SNMP TRAP:

from pysnmp.hlapi import *

errorIndication, errorStatus, errorIndex, varBinds = next(
    sendNotification(
        SnmpEngine(OctetString(hexValue='8000000001020304')),
        UsmUserData('usr-sha-aes128', 'authkey1', 'privkey1',
                    authProtocol=usmHMACSHAAuthProtocol,
                    privProtocol=usmAesCfb128Protocol),
        UdpTransportTarget(('demo.snmplabs.com', 162)),
        ContextData(),
        'trap',
        NotificationType(ObjectIdentity('SNMPv2-MIB', 'authenticationFailure'))
    )
)

if errorIndication:
    print(errorIndication)

We maintain publicly available SNMP Agent and TRAP sink at demo.snmplabs.com. You are welcome to use it while experimenting with whatever SNMP software you deal with.

$ python3 examples/hlapi/asyncore/sync/manager/cmdgen/usm-sha-aes128.py
SNMPv2-MIB::sysDescr.0 = SunOS zeus.snmplabs.com 4.1.3_U1 1 sun4m
$
$ python3 examples//hlapi/asyncore/sync/agent/ntforg/v3-inform.py
SNMPv2-MIB::sysUpTime.0 = 0
SNMPv2-MIB::snmpTrapOID.0 = SNMPv2-MIB::warmStart
SNMPv2-MIB::sysName.0 = system name

Other than that, PySNMP is capable to automatically fetch and use required MIBs from HTTP, FTP sites or local directories. You could configure any MIB source available to you (including this one) for that purpose.

For more example scripts please refer to examples section at pysnmp web site.

Documentation

Notes on library design and API could be read at pysnmp project site.

If something does not work as expected, open an issue at GitHub or post your question on Stack Overflow or try browsing pysnmp mailing list archives.

Finally, your PRs are warmly welcome! ;-)

Copyright (c) 2005-2017, Ilya Etingof. All rights reserved.