Python for network engineer:- Telnet to Cisco router using Python

Below script can be used to telnet Cisco router using Python script and can capture show version output.

import telnetlib # --<< importing telnet library

user = "test"   #--<< username configured in router

password = "test" #--<<Password configured in router

HOST = "192.168.1.100" #--<<IP address of the router

telnet = telnetlib.Telnet(HOST)

telnet.read_until("Username: ") # --<<Reading username from the router CLI screen

telnet.write(user + "\n") #--<< Configure username which is configured above

telnet.read_until("Password: ") #--<<Reading Password from the router CLI screen

telnet.write(password + "\n") #--<< Configure password which is configured above

telnet.write("terminal length 0\n") #--<< Configure command to capture the complete output

telnet.write("show version \n")  #--<<configure  show run

telnet.write("exit\n")  # --<<exit from the router

print telnet.read_all()  #-<<Read output from above show version command