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Our MPLS provider needs our routers to be setup with modems so that they can dial in and make config changes when necessary. I have connected the modem to the router (Cisco 2600) via the aux port. When I dial the # for the modem, it rings, but never answers. I'm guessing there's something in the router config that I need to setup, but I have no idea what it is. Any ideas?

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what kind of modem? – SpacemanSpiff Dec 4 '10 at 6:48
up vote 1 down vote accepted

The laziest way is almost certainly just to go:

async-1#terminal monitor
async-1#debug confmodem
Modem Configuration Database debugging is on
async-1#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
async-1(config)#line 1
async-1(config-line)#modem autoconfigure discovery

The real answer is set &S0=1 in your modemcap (well probably) Actually you probably want to look at the whole list of vendor init strings (that page also has some info on creating a chatscript and altering modemcaps)

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A couple of things to verify:

  • you are use a cisco roll-over cable
  • the modem speed
  • what TTY number is your aux port
  • configuration of your aux port

Additional information: Configuring a Modem on the AUX Port for EXEC Dialin Connectivity


line 65   
 modem inout
 speed 115200  
 transport input all
 flowcontrol hardware
 password cisco
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