Cool Cisco Aux->Console Trick

Post date: Oct 29, 2012 4:23:48 PM

Sometimes you just need to get into router, but can not telnet or ssh into it. You need console access. The only problem is that the router is in Maine, Northern Maine Luckily you have another router right next to it that you can get to. So here is how to get into the console

Using a rolled cable RJ-45 cable (1->8,2->7,3->6,4->5) connect the AUX port on one router to the Console port on the other and vice versa (2 cables between the 4 ports)

Then on each router configure:

line aux 0

password reddog50

login

modem InOut

no exec

transport preferred all

transport input all

transport output all

stopbits 1

You can then connect to the other routers console port using the command

telnet localIPaddress 2001

2001 is the TCP port number for the AUX port.

This is effectively using the AUX port on the router as a terminal server for access to the console port on the other router.