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Dialer DTR disconnects very quick

I have configured an interface with the following configuration:

interface Serial4<br>

ip address<br>

no ip directed-broadcast<br>

keepalive 60<br>

dialer dtr<br>

dialer idle-timeout 300<br>

dialer wait-for-carrier-time 60<br>

dialer-group 1<br>

no cdp enable<br>


dialer-list 1 protocol ip list 101<br><br>

The DDR seems to do what it should do, it dials when needed, but the modem hangs up while still dialing the number, or in or imediately after negotiation. Sometimes it passes this, and remains connected and works as needed. The problem is that the success rate is very low (about 1 of 10 tries). There are no line problems. Also, the modem seems fine (if i remove dialer dtr and the router keeps DTR up all time, the modems connect to each other and remain connected since the first try). The interface on the other router has only the ip address configured.


Re: Dialer DTR disconnects very quick

You can either try "debug serial inter"

to see what the physical signals are doing,

or get a break out box. The only control

the router has over the modem is via DTR;

if we are lowering DTR while the modem is

dialing, then the problem is at the cisco.

If DTR stays up while carrier drops, then

the problem is either the modem or the remote

end (in which case you would try the same

test at the remote end).

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