# Various SNMP versions

## SNMPv1

Send SNMP GET request using the following options:

- with SNMPv1, community ‘public’

- over IPv4/UDP

- to an Agent at demo.snmplabs.com:161

- for two instances of SNMPv2-MIB::sysDescr.0 MIB object,

- based on Twisted I/O framework

Functionally similar to:

$ snmpget -v1 -c public demo.snmplabs.com SNMPv2-MIB::sysDescr.0

    from twisted.internet.task import react
    from pysnmp.hlapi.twisted import *

    def success(args, hostname):
        (errorStatus, errorIndex, varBinds) = args

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

    def failure(errorIndication, hostname):
        print('%s failure: %s' % (hostname, errorIndication))

    # noinspection PyUnusedLocal
    def getSysDescr(reactor, hostname):
        d = getCmd(SnmpEngine(),
                   CommunityData('public', mpModel=0),
                   UdpTransportTarget((hostname, 161)),
                   ContextData(),
                   ObjectType(ObjectIdentity('SNMPv2-MIB', 'sysDescr', 0)))

        d.addCallback(success, hostname).addErrback(failure, hostname)

        return d

    react(getSysDescr, ['demo.snmplabs.com'])

`Download` script.

## Bulk walk MIB

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 past SNMPv2-MIB::system

- run till end-of-mib condition is reported by Agent

- based on Twisted I/O framework

Functionally similar to:

$ snmpbulkwalk -v3 -lnoAuthNoPriv -u usr-none-none -Cn0 -Cr50 demo.snmplabs.com SNMPv2-MIB::system

    from twisted.internet.task import react
    from pysnmp.hlapi.twisted import *

    def success(args, reactor, snmpEngine):
        (errorStatus, errorIndex, varBindTable) = args

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

            if not isEndOfMib(varBindTable[-1]):
                return getbulk(reactor, snmpEngine, *varBindTable[-1])

    def failure(errorIndication):
        print(errorIndication)

    def getbulk(reactor, snmpEngine, varBinds):
        d = bulkCmd(snmpEngine,
                    UsmUserData('usr-none-none'),
                    UdpTransportTarget(('demo.snmplabs.com', 161)),
                    ContextData(),
                    0, 50,
                    varBinds)
        d.addCallback(success, reactor, snmpEngine).addErrback(failure)
        return d

    react(getbulk, [SnmpEngine(), ObjectType(ObjectIdentity('SNMPv2-MIB', 'system'))])

`Download` script.

See also: library reference.