Physical Set Up
Use a standard Cisco console cable or create a cable with the following DB9 to RJ-45 connections.
Connect the rollover UTP cable to the router A AUX port and DB9 connector to the router B's console port.
Proceed to the router configuration in the next section.
RJ-45 Adapter Pinouts to DB9 DCE (non-modem)
From Cisco A AUX port to Router B (or other standard DB9 console port) using straight UTP cable
AUX Port | Color | Assignments | DCE Style (non-modem) DB9 Pinouts | Assignments |
1 | Blue | RTS(out) | 8 | CTS (Clear To Send) |
2 | Orange | DTR(out) | 6 | DSR (Data Send Ready) |
3 | Black | TX+(out) | 2 | RXD |
4 | Red | TX- | 5 | GND |
5 | Green | RX- | 5 | GND |
6 | Yellow | RX+(in) | 3 | TXD |
7 | Brown | DSR(in) | 4 | DTR (Data Terminal Ready) |
8 | White/Grey | CTS | 7 | RTS (Ready-To-Send) |
Router Configuration
1. Determine the line number for the AUX port on your router.
For example:
# sh line
Tty Line Typ Tx/Rx A Modem Roty AccO AccI Uses Noise Overruns Int
0 0 CTY - - - - - 0 0 0/0 -
1 1 AUX 9600/9600 - inout - - - 0 0 0/0 -
* 194 194 VTY - - - - - 3 0 0/0 -
195 195 VTY - - - - - 0 0 0/0 -
196 196 VTY - - - - - 0 0 0/0 -
197 197 VTY - - - - - 0 0 0/0 -
198 198 VTY - - - - - 0 0 0/0 -
2. Define a loopback for reverse Telnet and IP host using TTY number from Step 1.
ip host rtsh1 2001 10.10.10.1
!
interface Loopback0
ip address 10.10.10.1 255.255.255.255
3. Setup aux 0 for reverse telnet.
line aux 0
modem InOut
no exec
transport input all
transport output all
stopbits 1
4. Telnet to the router loopback interface and port. (2000 + Aux line number)
For example: telnet 10.10.10.1 2001
Referance: