How to configure the AUX port on an ASA5520 to be setup for dial backup with a modem like a router

[TCC_2]

Core issue

You cannot use the AUX port available on the ASA in order to connect to the modem. But, you can use console port to connect the modem.

Resolution

Complete these steps in order to use the console port to connect the modem:

If a PC is used to configure the modem, use hyper terminal with the speed set for 9600 baud.

1. Use this init string in order to initialize the modem:
   
   AT&FS0=1&C1&D2&H0&R1&B1&M4&K0&N6&W. 
   
   An OK from the modem appears.
   
   
2. Enter this init string also in order to disable Echo and result codes:
   
   ATE0Q1&W
   
   
3. Change the modem dip switches to 4 and 8 down and power cycle the modem.
   
   
4. Remove the cable from the PC and connect it to console port.
   
   
5. No configuration is required on the console.

Note: Use the standard Cisco Rolled Cable along with the modem adapter.

The modem settings work for US robotic.

Refer to ASA: Attach a US Robotics Modem to the Console Port for more information.