Legacy script checking switch port status via snmp

gistfile1.txt

from pysnmp.entity.rfc3413.oneliner import cmdgen

#################################################################################################
# Global Settings
deviceIPAddress = "10.12.250.1"
snmpPort = 161
snmp_username = "monitoring"
# Port Status Displayed Information
statusID = {1: "Disabled", 
            2: "Blocking", 
            3: "Listening", 
            4: "Learning",
            5: "Forwarding", 
            6: "Broken"}


#################################################################################################

def get_if_names():
    interface_names = {}
    username = '%s@%s' % (snmp_username, 1)
    error_indication, \
    error_status, \
    error_index, \
    var_binds = cmdgen.CommandGenerator().nextCmd(
        cmdgen.CommunityData('agent', username, 0),
        cmdgen.UdpTransportTarget((deviceIPAddress, snmpPort)),
        (1, 3, 6, 1, 2, 1, 31, 1, 1, 1, 1))
    for row in var_binds:
        interface_index = str(row[0][0]).split('.')[-1]
        port, _, number = str(row[0][1]).rpartition('/')
        name = port + '/' + number.zfill(2)
        interface_names[interface_index] = name
    return interface_names


def get_if_index(vlan, snmp_username):
    interface_index = {}
    username = '%s@%s' % (snmp_username, vlan)
    error_indication, error_status, error_index, var_binds = cmdgen.CommandGenerator().nextCmd(
        cmdgen.CommunityData('agent', username, 0),
        cmdgen.UdpTransportTarget((deviceIPAddress, snmpPort)),
        (1, 3, 6, 1, 2, 1, 17, 1, 4, 1, 2))
    for row in var_binds:
        number = str(row[0][0])
        index = str(row[0][1])
        interface_index[number] = index
    return interface_index


def get_bridge_ports(vlan, snmp_username):
    bridge_port = {}
    username = '%s@%s' % (snmp_username, vlan)
    error_indication, error_status, error_index, var_binds = cmdgen.CommandGenerator().nextCmd(
        cmdgen.CommunityData('agent', username, 0),
        cmdgen.UdpTransportTarget((deviceIPAddress, snmpPort)),
        (1, 3, 6, 1, 2, 1, 17, 4, 3, 1, 2))
    for row in var_binds:
        name = str(row[0][0])
        port = str(row[0][1])
        bridgePort[name] = port
    return bridgePort


def get_macs(vlan, snmp_username):
    macs = {}
    username = '%s@%s' % (snmp_username, vlan)
    error_indication, error_status, error_index, var_binds = cmdgen.CommandGenerator().nextCmd(
        cmdgen.CommunityData('agent', username, 0),
        cmdgen.UdpTransportTarget((deviceIPAddress, snmpPort)),
        (1, 3, 6, 1, 2, 1, 17, 4, 3, 1, 1))
    for row in var_binds:
        name \
            = '1.3.6.1.2.1.17.4.3.1.2.' + '.'.join(
                str(row[0][0]).split('.')[-6:])
        mac = row[0][1]
        mac = ':'.join(['%02x' % ord(x) for x in mac])
        macs[mac] = name
    return macs


def get_arp():
    ips = {}
    username = snmp_username
    error_indication, error_status, error_index, var_binds = cmdgen.CommandGenerator().nextCmd(
        cmdgen.CommunityData('agent', username, 0),
        cmdgen.UdpTransportTarget((deviceIPAddress, snmpPort)),
        (1, 3, 6, 1, 2, 1, 3, 1, 1, 2))
    for row in var_binds:
        ip = '.'.join(str(row[0][0]).split('.')[-4:])
        mac = row[0][1]
        mac = ':'.join(['%02x' % ord(x) for x in mac])
        ips[mac] = ip
    return ips


# Retrieve VLAN Table
error_indication, error_status, error_index, var_binds = cmdgen.CommandGenerator().nextCmd(
    cmdgen.CommunityData('agent', snmp_username, 0),
    cmdgen.UdpTransportTarget((deviceIPAddress, snmpPort)),
    (1, 3, 6, 1, 4, 1, 9, 9, 46, 1, 3, 1, 1, 2))

# Store VLAN Table
vlans = []
for row in var_binds:
    for item in row:
        vlans.append(item[0][15])

switch = {}
ips = get_arp()
interface_names = get_if_names()
for vlan in vlans:
    interface_index = get_if_index(vlan, snmp_username)
    bridge_ports = get_bridge_ports(vlan, snmp_username)
    macs = get_macs(vlan, snmp_username)
    for mac, bridgePort in macs.iteritems():
        switch[interface_names[
            interface_index['1.3.6.1.2.1.17.1.4.1.2.' + bridge_ports[bridgePort]]]] = (
        mac, vlan)

for port in sorted(switch):
    try:
        print "Port {0} has connected mac :{1} with ip : {2} on vlan {3}".format(
            port, switch[port][0], ips[switch[port][0]], switch[port][1])
    except KeyError:
        print "Port {0} has connected mac :{1} on vlan {2}".format(port,
                                                                   switch[port][
                                                                       0],
                                                                   switch[port][
                                                                       1])