You have a Cisco device (router or switch) and you want to connect to it via the console cable, but you do not know how to do this. In this post, I will show you the step-by-step process.
Table of Contents
Buy a USB console cable
In my example I will use a USB console cable. You can buy a similar one from here.
Connect the console cable to your router
After you have the console cable, the next step is to connect the USB end of the cable to your computer and the RJ45 end of the cable to the Cisco router. On the router or switch you will find a port which is labeled as console. You can find an example below. In my lab, I use a Cisco 2911 Router. The model of the router or switch does not matter. You need to take the same steps.
Turn on the router
After the cable is connected, you need to turn on the router. There is a power switch on the router. You do not have one on the Cisco switches. The Cisco switches are starting to boot as soon as you plug them to the power outlet.
Check the allocated TTY port
After the router is up and running, you need to check which TTY port was allocated by your operating system to the USB port where the cable is connected.
Run this command:
sudo dmesg | grep -i USB | tail
A similar command which gives us approximately the same result is:
ls -l /dev/*USB*
Install the required software and configure the connection
Now, you need to configure the connection and start it. You can use two methods for this.
Method 1: Using Minicom software
You need to install minicom because it is not present by default on the Ubuntu host.
Run the command:
sudo apt-get install minicom
After the minicom package is installed, you need to configure the connection.
sudo minicom -s
Go to the serial port setup. You need to use the Up and Down arrow keys.
Specify the serial device by pressing A and add the details from “Check the allocated TTY port”step.
Specify the Bps/Par/Bits by pressing the E key and select the option C. You need to use the speed 9600.
Change the hardware flow to no. Press the F key to change it from Yes to No.
Press the Esc key to go to the main window. Here you have the possibility to save the changes. Select the option Save setup as DFL and hit the Enter key.
The last step is to press Exit. Now you can start configuring your device.
Here you can see the output from my Cisco router.
Method 2: Using Screen software
The same result can be achieved by using the screen program.
First, you need to install it with the below command:
sudo apt-get install screen
After the screen software is installed, you need to open the program and specify the connection speed to 9600. Don’t forget to hit the Enter key.
screen /dev/ttyUSB0 9600
Now, you can start to explore and configure your Cisco router.
Connect your Cisco router via the console cable on your Mac
If you do not use Linux, but macOS, there is no need to panic. The same process applies to your Mac.
The first step is to identify the TTY port.
Now, you just need to run the screen program. The screen package is installed by default on your macOS.
screen /dev/tty.usbserial-A50285BI 9600
Now you can start configuring your router.
Connect your Cisco router via the console cable on your Windows host
If you use Windows, the process is somewhat different.
You need to download the Putty software. You can find the link here.
The next step is to install the downloaded software. Double click on the putty-64bit-0.78-installer.msi and press Next until the installation process is completed.
Now, you need to open the Putty application.
The next step is to identify the serial port allocated by Windows to your USB cable. Open the Computer Management console. Go to the Device Manager. Check the Ports. In my lab, Windows allocated the COM3 port to my USB cable.
Return to the Putty application, select the connection type as Serial and specify the allocated port. I added COM3.
Next, press the Open button and start configuring your device.
I hope you find this post useful.