check_ibgp.py

#!/usr/bin/env python
#
# @descr    Checks iBGP status of Cisco IOS devices
#
# @author   Johan Hedberg <jh@citynetwork.se>
#

import sys
import argparse
from lib.cnh_nm import STATE_OK, STATE_WARN, STATE_CRIT
from lib.cnh_nm import my_snmp_get, snmpresult_to_dict, my_snmp_walk, snmp_oid_decode_ip
from lib.cnh_nm import trigger_not_ok, check_if_ok


# Argument parsing
parser = argparse.ArgumentParser(description='Check iBGP session status')
parser.add_argument('-C', metavar='<community>', required=True,
                    help='SNMP Community')
parser.add_argument('-H', metavar='<host>', required=True,
                    help='Host to check')
args = parser.parse_args()


# Get local AS number
local_as = my_snmp_get(args, 'BGP4-MIB::bgpLocalAs.0').value


# Get all BGP peers
oids = [
    'CISCO-BGP4-MIB::cbgpPeer2RemoteAs',
    'CISCO-BGP4-MIB::cbgpPeer2AdminStatus',
    'CISCO-BGP4-MIB::cbgpPeer2LastErrorTxt',
    'CISCO-BGP4-MIB::cbgpPeer2State'
]
rawdata = my_snmp_walk(args, oids)
data = snmpresult_to_dict(rawdata)


# Now loop over data, and for _iBGP_ check the states
status = STATE_OK
statusstr = ""
num_ibgp = 0
for index, peer in data.iteritems():
    if local_as not in peer['cbgpPeer2RemoteAs'].value:
        continue
    num_ibgp += 1
    peer_ip = snmp_oid_decode_ip(index)
    admin_state = int(peer['cbgpPeer2AdminStatus'].value)
    bgp_state = int(peer['cbgpPeer2State'].value)
    last_error = peer['cbgpPeer2LastErrorTxt'].value.strip()
    if not last_error:
        last_error = "None"
    if admin_state == 1:  # Down
        status, statusstr = trigger_not_ok(
            status,
            statusstr,
            STATE_WARN,
            "{} admin down".format(peer_ip))
        continue
    if bgp_state in [0, 1, 2, 3, 4, 5]:  # none/idle/connect/active/opensent/openconfirm
        status, statusstr = trigger_not_ok(
            status,
            statusstr,
            STATE_CRIT,
            "{} BGP session down (Last error: {})".format(peer_ip, last_error))
        continue


# All checks completed, exiting with the relevant message
check_if_ok(status, statusstr)

print "OK: All ({}) iBGP sessions established".format(num_ibgp)
sys.exit(STATE_OK)