Multithreading enables CPUs to run different parts(threads) of a process concurrently. The threading module comes with the standard Python library.
Automation of networking is always comes with scale requirement, manage or connect or capture data from so many devices, create reports of each device in separate files etc.
from netmiko import ConnectHandler
from datetime import datetime
from threading import Thread
startTime = datetime.now()
threads = []
def checkparallel(ip):
device = ConnectHandler(device_type='cisco_ios', ip=ip,username='test', password='test')
output = device.send_command("show run | in hostname")
output=output.split(" ")
hostname=output[1]
print ("\nHostname for IP %s is %s" % (ip,hostname))
for n in range(1, 5):
ip="192.168.20.{0}".format(n)
t = Thread(target=checkparallel, args= (ip,))
t.start()
threads.append(t)
for t in threads:
t.join()
print ("\nTotal execution time:")
print(datetime.now() - startTime)
Creating loopback interface
from netmiko import ConnectHandler
from threading import Thread
from pysnmp.entity.rfc3413.oneliner import cmdgen
cmdGen = cmdgen.CommandGenerator()
threads = []
def checkloopback45(ip,interface):
loopbackpresent=False
cmdGen = cmdgen.CommandGenerator()
errorIndication, errorStatus, errorIndex, varBindTable =cmdGen.bulkCmd( cmdgen.CommunityData('mytest'),
cmdgen.UdpTransportTarget((ip, 161)), 0,25, '1.3.6.1.2.1.2.2.1.2' )
for varBindTableRow in varBindTable:
for name, val in varBindTableRow:
if (interface in val.prettyPrint()):
loopbackpresent=True
break
if loopbackpresent:
print ("\nFor IP %s interface %s is present" % (ip,interface))
else:
print ("\nFor IP %s interface %s is NOT present. Pushing the config" % (ip,interface))
pushconfig(ip,interface)
for n in range(1, 5):
ip="192.168.20.{0}".format(n)
thread = Thread(target=checkloopback45, args= (ip,"Loopback45",))
thread.start()
threads.append(thread)
for t in threads:
t.join()
This configuration will be pushed to each router from Netmiko.The code to identify the routers on which the configuration is missing, and update accordingly, is as follows:
from netmiko import ConnectHandler
from threading import Thread
from pysnmp.entity.rfc3413.oneliner import cmdgen
cmdGen = cmdgen.CommandGenerator()
threads = []
def pushconfig(ip,interface):
print ("\nConfiguring router %s now..." % (ip))
device = ConnectHandler(device_type='cisco_ios', ip=ip,username='test', password='test')
configcmds=["interface "+interface, "description "+interface+" test interface created"]
device.send_config_set(configcmds)
checkloopback45(ip,interface)
def checkloopback45(ip,interface):
loopbackpresent=False
cmdGen = cmdgen.CommandGenerator()
errorIndication, errorStatus, errorIndex, varBindTable =cmdGen.bulkCmd(
cmdgen.CommunityData('mytest'),
cmdgen.UdpTransportTarget((ip, 161)), 0,25, '1.3.6.1.2.1.2.2.1.2' )
for varBindTableRow in varBindTable:
for name, val in varBindTableRow:
if (interface in val.prettyPrint()):
loopbackpresent=True
break
if loopbackpresent:
print ("\nFor IP %s interface %s is present" % (ip,interface))
else:
print ("\nFor IP %s interface %s is NOT present. Pushing the
config" % (ip,interface))
pushconfig(ip,interface)
for n in range(1, 5):
ip="192.168.20.{0}".format(n)
t = Thread(target=checkloopback45, args= (ip,"Loopback45"))
t.start()
threads.append(t)
for t in threads:
t.join()
