How to connect a terminal to the console port from GNU/Linux or Windows

Connect Serial Cable to Console Port

The connection to the console port of a device allows to configure it in CLI during a first startup or if remote accesses are not available (ssh, http etc…).

Nowadays most serial cables use the USB interface to be connected to the computer. On the devices side (switchs, routers etc…), the connection is made via a classic console port, USB or mini USB.

GNU/Linux

First plug the USB cable to your computer.

Install screen

screen is a terminal wich will make us able to connect to our USB-to-serial converter.

• Install screen software :

root@host:~# apt update && apt install screen

Identify USB device

• Retrieve device name :

root@host:~# dmesg | grep -i "serial.*tty" 
[33994.065881] usb 2-1: FTDI USB Serial Device converter now attached to ttyUSB0

Connect

• In most cases you will be able to connect with this command (you can specify 300, 1200, 9600 (default), 19200, or 115200 as baud rate) :

user@client:~$ screen /dev/ttyUSB0 115200

• You can also specify transmission options if needed cs8 or cs7 (Specify the transmission of eight (or seven) bits per byte) :

user@client:~$ screen /dev/ttyUSB0 115200,cs8

Windows

First plug the USB cable to your computer.

Device Manager

• Open Device Manager to retrieve the Serial line name :

Putty

• Download putty.exe here : www.chiark.greenend.org.uk

• Open putty.exe and configure Serial menu whith information retrieved, then click Open to connect :

Tera Term (Putty alternative)

As a good alternative to Putty, we can also use Tera Term.

• Download Tera Term here : https://osdn.net/ (I personnaly download the portable zip archive) :

• Unzip and run ttempro.exe :

• Select Serial, your USB serial port and click OK :