Managing Cisco Routers / Switches with Python, Take 2

Here is my script to date. It's functional and works pretty well, in my limited testing.

I'll put my future revisions on github.com/jtdub/pyMultiChange

#!/usr/bin/env python

import getpass, sys, telnetlib, os, argparse

# Variables
tacacs = '.tacacslogin'
verbose = False
devicetype = 'ios'
hostsfile = ''
commandsfile = ''

def main():
# Parse and display argument variables
global verbose, devicetype, hostsfile, commandsfile
parser = argparse.ArgumentParser(description='Managing Cisco routers/switches with Python')
parser.add_argument('-d', '--hosts', help='Specifies a host file')
parser.add_argument('-c', '--commands', help='Specifies a commands file', required=True)
parser.add_argument('-v', '--verbose', help='Be verbose with command output')
parser.add_argument('-n', '--nexus', help='Execute script assuming Nexus hosts')

args = vars(parser.parse_args())

if args['hosts']:
hostsfile = args['hosts']
if args['commands']:
commandsfile = args['commands']
if args['verbose']:
args['verbose'] = True
verbose = args['verbose']
if args['nexus']:
devicetype = 'nexus'

return hostsfile, commandsfile, devicetype, verbose

main()

def userlogin():
# Getting login credentials
global username, password, enable
if os.path.isfile(tacacs):
login = open(tacacs, "r")
username = login.readline()
username = username.replace("\n", "")
password = login.readline()
password = password.replace("\n", "")
enable = login.readline()
enable = enable.replace("\n", "")
login.close()
else:
print tacacs, "not found.\n"
username = raw_input("Username: ")
password = getpass.getpass("User Password: ")
enable = getpass.getpass("Enable Password: ")

return username, password, enable

def login(devicetype):
# Logging in with username, password, and eable password
global username, password, enable
if devicetype == "nexus":
telnet.read_until("Login: ")
telnet.write(str(username) + "\n")
else:
telnet.read_until("Username: ")
telnet.write(str(username) + "\n")

if password:
telnet.read_until("Password: ")
telnet.write(str(password) + "\n")

if devicetype == "ios":
if enable:
telnet.read_until(host2login + '>')
telnet.write("enable\n")
telnet.read_until("Password: ")
telnet.write(str(enable) + "\n")

def sessioncommands():
# Executing commands on the host
global commands
print "Executing Commands on", host2login
if os.path.isfile(commandsfile):
commands = open(commandsfile, "r")
try:
for cmd2exe in commands:
telnet.write(cmd2exe)
finally:
commands.close()
else:
print commandsfile, " doesn't exist"
telnet.write("exit\n")
# Displaying the results
if verbose == True:
output = telnet.read_all()
if "% " in output:
print "Error: ", output
sys.exit()
else:
print output

print "Logging out of", host2login

# Doing work
userlogin()
if os.path.isfile(hostsfile):
hosts = open(hostsfile, "r")
while 1:
host2login = hosts.readline()
host2login = host2login.replace("\n", "")
print "Logging into", host2login
if not host2login:
break
else:
telnet = telnetlib.Telnet(host2login)
login(devicetype)
sessioncommands()
hosts.close()
else:
host2login = raw_input("Host: ")
print "Logging into", host2login
telnet = telnetlib.Telnet(host2login)
login(devicetype)
sessioncommands()