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having problems with modem connection to aux port on 7200VXR

I have a US Robotics modem connected to a 7200VXR aux port. I dial in

and get a connection, but no response.

We setup line aux 0

modem inout

transport input all

flowcontrol hardware

Is there something I am missing?

Just to check the aux port, can we do a direct hypterm connection to the aux port from

a laptop using just the RJ-45 rollover cable?

Any help would be appreciated


Re: having problems with modem connection to aux port on 7200VXR

Can you reverse telnet into the modem connected off the aux port?

telnet x.x.x.x 2yyy or [2000+yyy]

The x.x.x.x represents the IP address of any up/up interface on the router (for example, an Ethernet or Loopback) and yyy is the line number to which you want to connect. If the TTY line has already been configured, you can issue the telnet command from anywhere on the network that can ping the x.x.x.x interface.

Can you try adding the following init string in the USR modem after reverse telnetting to it.

With dip switches 3&8 down rest up.....AT&F1S0=1&C1&D2&A1&W

Also ensure the cabling is correct...Also try changing the speed under the line if the above does not work.

Thanks, Mak.

Cisco Employee

Re: having problems with modem connection to aux port on 7200VXR

I think the AUX port of the router is working ok. The reason for that is you do get a succesful modem connection. Now here is the link which discuss the config and troubleshooting the modem on AUX port

The config that you have is fine. Try to add "modem autoconfigure discovery" and "speed 38400" under the line config. After that issue "clear line aux 0" so that router try to detect the modem on the aux port.

Also make sure that the dip switches on the back of USR modem set to 3 and 8 downword and rest all should be set to upword direction.