Cisco Serial-USB

If you want to connect your computer and a cisco device (fe router, switch…) with a usb-cable instead of a serial-cable, you can use following steps under linux to connect it properly

Check with the command ‘dmesg’ in a terminal screen the correct address. Do this just after inserting the usb-cable.

[ 2663.068216] usb 1-3.3: new full speed USB device using ehci_hcd and address 9
[ 2663.169789] cdc_acm 1-3.3:1.0: This device cannot do calls on its own. It is not a modem.
[ 2663.169839] cdc_acm 1-3.3:1.0: ttyACM0: USB ACM device

In our example, this is ttyACM0
Open now your ‘configuration program’ (fe putty) and insert following port as ‘serial’:


That’s it…