REVERSE TELNET ON AUX PORT

 Requirement : 

Need  to  configure  reverse telnet  via  AUX  port. Connect one router's aux port to another device's console port, and telnet to the router.Use reverse telnet to connect to the other device's console via your aux port

 Setup  : 

Here's how to set it up.

1.      Connect your router's aux port to another device's console port using a Cisco flat crossover cable.

2.      Telnet to your router, enable, and set the aux port up as follows:

 R1#conf t

R1(config)# line aux 0

R1(config-line)# modem InOut

R1(config-line)# transport preferred all

R1(config-line)# transport input all

R1(config-line)# transport output all

R1(config-line)# end

3.      Make sure you have an address on your lo0 interface, and the interface is up.

R1#conf t

R1(config)#int  lo0

R1(config-if)#ip  add  127.0.0.1 255.255.255.0

Execution :

1)      Come back in enable mode, find out the line number of your AUX port with “show  line”. It will look something like this. On this router it is line 1. It's different from router to router.

               R1#show  line

               Tty Type     Tx/Rx    A Modem

    0 CTY              -    -

  * 1 AUX   9600/9600  - inout

  * 2 VTY              -    -

   3 VTY              -    -

   4  VTY              -    -

   5  VTY              -    -

   6  VTY              -    -

2)  Add 2000 to the line number, and telnet to your lo0 address i.e 127.0.0.1 , port 2001.

3)      Just connect the router's aux port to the target device.

4)      From the command line on the router, type “telnet 127.0.0.1 2001. This gives you a console connection to the target device.

5)      To end the connection, type

Shift+ctrl+6+x,  then type “clear  line  x” OR Shift+ctrl+6+x then  type “dc”