How to make your Cisco router a terminal server

Bill — Fri, 10 Jul 2009 17:09:14 +0000

On more than one occasion I have needed to access the console port of a switch, but I wasn’t physically there but I did have a router near the unit. You can easily setup your router to act as a Terminal server, allowing you to use a flat rolled cable between the Router’s AUX port and the switch’s CONSOLE port. First you need to properly configure your AUX port:

line aux 0
    modem InOut
    transport input all
    stopbits 1
   flowcontrol hardware

Now in order to use this feature, log into your router and do the following:

from the command prompt enter: SHOW LINE
Find the line number for AUX (in this example it is Line 5)
Telnet to the IP address of the router you are logged into, but when you telnet you will need to indicate a specific port. That port is 2000 + the line number. So in this example your command would look like this: ‘telnet 172.17.10.1 2005′
This will get you access to the remote device
When you are finished with the session on the remote device break out with CTRL+ALT+6, followed by x one second later. If you by chance use SecureCRT for your Telnet sessions you can setup a key map that sends the following ASCII standard for that command ‘\036\px’. You can read more about this on VanDyke’s SecureCRT Forum.
Once you are back in the original device you can return to the remote device by simply pressing the ENTER key.
If you are finished with your remote session, you can issue a CLEAR command to close that connection. In this example the command would be ‘CLEAR LINE 5′

Helpful Cisco Documents

Bill — Thu, 11 Jun 2009 13:28:33 +0000

I always need to look up features on different Cisco routers and switches. Cisco actually produces two documents that let you quickly see all the available models and associated features:

Cisco Router Guide
Cisco Catalyst Switch Guide

#SH RUN » router

How to make your Cisco router a terminal server

Helpful Cisco Documents