Connecting to Cisco console with Linux

Table of contents

  1. screen (VT100/ANSI terminal emulation)
  2. Identify USB-to-Serial adapter
  3. Connect with console cable

screen (VT100/ANSI terminal emulation)

I have an older Lenovo ThinkPad running with Linux and sometimes I need to connect with a serial console to Cisco hardware (instead of using SSH via network). The ThinkPad T520 does not have a serial port and therefore I am using a cheap USB-2-Serial adapter.

I was looking for a quick method to connect to Cisco hardware with Linux - instead of Windows and PuTTY - and I figured out that screen works perfectly. screen is a screen manager with VT100/ANSI terminal emulation.

Identify USB-to-Serial adapter

First I figure out which device is used by the USB-to-Serial adapter. I’m doing it with dmesg and grep as shown below:

    str@ThinkPad-T520:~$ dmesg | grep ttyUSB
    [12069.219496] usb 2-1.1: pl2303 converter now attached to ttyUSB0

Connect with console cable

Then I’m using screen (must be root or called with sudo) and the device from the dmesg output:

    str@ThinkPad-T520:~$ sudo screen /dev/ttyUSB0

As you can see, it works perfectly to connect with my Linux laptop to my Cisco wireless controller:

Cisco console with Linux