How to fix and add SSH and config code for Cisco router

Question

The following is my code to remotely connect to a network device (Cisco router). Currently, it is not functional, but I don’t see any errors. It also needs to be able to configure a loopback and at least one other interface with an appropriate IP address on a router within your topology. Configure OSPF protocol on a network device within the topology and advertise appropriately.

I have tried to run the code on Netlab to connect to the router remotely. The connection initially works, but times out. I assume the commands I am sending over are coded incorrectly.

When running the code and after entering the username, password and SSH choice, I received this response.

INFO:paramiko.transport:Connected (version 1.99, client Cisco-1.25)
INFO:paramiko.transport:Authentication (password) successful!
INFO:root:Connection established
ERROR:root:An error occurred: Timed-out reading channel, data not available.
INFO:root:The connection has concluded

I am also reviving the message the the line of net_connect.disconect() might be undefined.

Any help would be greatly appreciated.

    #Getting imports

    from netmiko import ConnectHandler
    import getpass
    import difflib
    import logging

    #Logging

    logging.basicConfig(level=logging.INFO)

    #Saving config

    def save_config_to_file(config, filename):
        with open(filename, 'w') as config_file:
            config_file.write(config)
        logging.info(f'Configuration saved to {filename}')

    #Displaying differences

    def show_differences(config1, config2):
        difference = difflib.Differ()
        diff = list(difference.compare(config1.splitlines(), config2.splitlines()))

        for line in diff:
            if line.startswith('- '):
                logging.info(f'Present in ({config1}): {line[2:]}')
            elif line.startswith('+ '):
                logging.info(f'Present in ({config2}): {line[2:]}')

    #Config commands

    def configure_device(net_connect):
        loopback_config = [
            'en\n'
            'conf t\n'
            'interface Loopback0\n',
            'ip address 192.168.57.101 255.255.255.0\n',
            'exit\n'
        ]

        acl_config = [
            'ip access-list extended MY_ACL\n',
            'permit ip 192.168.56.130 255.255.255.0 any\n',
            'deny ip any any\n',
            'exit\n'
        ]

        interface0_config = [
            'interface GigabitEthernet0/0\n',
            'ip address 192.168.58.101 255.255.255.0\n',
            'exit\n'
        ]

        interface1_config = [
            'interface GigabitEthernet0/1\n',
            'ip address 192.168.59.101 255.255.255.0\n',
            'exit\n'
        ]
        configs = loopback_config + acl_config + interface0_config + interface1_config
        output = net_connect.send_config_set(configs)
        print(output)

    #User info and choice of connection type

    def main():
        host = '192.168.56.101'
        username = input('Please enter your username: ')
        password = getpass.getpass('Please enter your password: ')
        secret = 'cisco'

        choice = input('Would you like to connect by using telnet or ssh? ')

        if choice.lower() == 'telnet':
            device_type = 'cisco_ios_telnet'
        elif choice.lower() == 'ssh':
            device_type = 'cisco_ios'
        else:
            raise ValueError('Invalid - Please choose either telnet or ssh: ')

        device = {
            'device_type': device_type,
            'host': host,
            'username': username,
            'password': password,
            'secret': secret,
            'port': 22 if device_type == 'cisco_ios' else 23,
            'timeout': 100,
        }

    #Connecting to device

        try:
            with ConnectHandler(**device) as net_connect:
                logging.info('Connection established')

    #Sending config commands

                configure_device(net_connect)

    # Saving config
                running_configuration = net_connect.send_command('show running-config')
                local_config_file_name = 'local_config.txt'
                save_config_to_file(running_configuration, local_config_file_name)
                logging.info(f'The configuration has been saved to {local_config_file_name}')

    #comaprign config

                local_config_file_name = 'local_config.txt'

                try:
                    with open(local_config_file_name, 'r') as local_config_file:
                        local_config = local_config_file.read()

                    if running_configuration and local_config:
                        if running_configuration == local_config:
                            logging.info('The running configuration is the same as the local configuration')
                        else:
                            logging.warning('The running configuration does not match the local configuration: ')
                            show_differences(running_configuration, local_config)
                    else:
                        logging.error('Failed to access configurations')

                except FileNotFoundError:
                    logging.error(f'The local configurations file, ({local_config_file_name}), could not be found')

        except Exception as e:
            logging.error(f'An error occurred: {e}')

    #Ending connection

        logging.info('The connection has concluded')
        net_connect.disconnect()

    if __name__ == "__main__":
        main()

GitHub link to code - https://github.com/louisw16/Programming-For-Networking-Engineers/blob/main/A3.py

Thank you

Answer 1

You don't need to worry about entering configuration mode. root of your problem is:

            'en\n'
            'conf t\n'

Short example based on your code:

import logging
import getpass

from netmiko import ConnectHandler

logging.basicConfig(level=logging.INFO)


def configure_device(net_connect):
    """Config commands"""
    loopback_config = [
        'interface Loopback0\n',
        'ip address 192.168.57.101 255.255.255.0\n',
    ]
    configs = loopback_config
    output = net_connect.send_config_set(configs)
    print(output)


def main():
    host = '192.168.56.101'
    username = input('Please enter your username: ')
    password = getpass.getpass('Please enter your password: ')
    secret = 'cisco'

    device = {
        'device_type': 'cisco_ios',
        'host': host,
        'username': username,
        'password': password,
        'secret': secret,
        'timeout': 100,
    }

    # Connecting to device
    try:
        with ConnectHandler(**device) as net_connect:
            logging.info('Connection established')

            # Sending config commands
            configure_device(net_connect)

    except Exception as e:
        logging.error(f'An error occurred: {e}')


if __name__ == '__main__':
    main()