device_type: cisco_ios_serial error using USB mini-Type B

Hello @ktbyers

In some models of Cisco devices, you can find a USB mini-Type B console port on the front of the device which lets you connect serially to that device. When I am connected to a Cisco device using that Type B console cable and trying to initiate a serial connection instance, I get an error. But when I use a standard Cisco console cable (RJ-45), it works like a charm. I don’t know what is the problem with the Type B cable?

I know the two cables work with different technologies. But what is the issue in this case?

The error I get:

$ python serial_conn.py
Timed-out reading channel, pattern not found in output: terminal\ length\ 0

Router prompt not found: 'switch_'

Code sample:

#!usr/bin/env python3

from netmiko import ConnectHandler as CH
from pprint import pprint

# Define a device
device = {
    "device_type": "cisco_ios_serial",
    "ip": "10.1.1.1",
    "username": "cisco",
    "password": "cisco",
    "serial_settings": {
        "port": "COM4",
    },
}

# Initiate a serial connection instance to device
with CH(**device) as net_connect:
    output = net_connect.send_command("show version", use_textfsm=True)
pprint(output)

[ktbyers]

cisco_ios overwrites the default and sets it to True (in its class).

https://github.com/ktbyers/netmiko/blob/v3.4.0/netmiko/cisco/cisco_ios.py#L15

Note, I just changed some of this behavior in the Netmiko develop branch, but this is True for Netmiko version 3.4.0 which is what is released on pypy (and version 3.4.0 is also what I linked to above).

[Tes3awy]

I tried using send_command_timing("show version", use_textfsm=True) instead and it worked. But there is something I noticed which is weird to me. I also had to explicitly set "fast_cli": False!!. Without "fast_cli": False, I got the same error. However; I can see in the BaseConnection class that fast_cli has False as its default value. (I am using Netmiko v3.4.0)