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New Member

Analogue and Digital callback

Have a 3640 with an NM-8AM and 8port Bri Module, the customer as added a digital modem pack to accomodate ISDN remote users.(With a view to change to a PRI circuit and removing 8AM) He requires callback to the digital modem users but cant get any of the configs to work. Callback works Ok with the analogue but not the digital. They can dial in but not get callback. Yes the windows client software is configured to accept callback also

Following is config for the digital callback

Username YYYY callback-dialstring XXXX password ZZZZZZ

interface BRI2/4

no ip address

dialer pool-member 3

isdn switch-type basic-net3

isdn incoming-voice modem

encapsulation ppp

ppp authentication ms-chap chap

ppp callback accept

interface DialerX

description Digital Modem Access User1

dialer string xxxx

ppp callback accept

dialer enable-timeout 2

dialer pool 3

ppp authentication ms-chap chap

Any Ideas


Cisco Employee

Re: Analogue and Digital callback

I assume that you want users using analog modem dialin to 3600 over bri line terminating on digital mica modems and get called back..

You need to create "interface group-async 1" and apply all the config there..

Once the call received on bri interface will be punt to modems on interface group-async x interface..

Here is a sample config for that.

just enter the required callback commands under the interface group-async 1like documented under following url

New Member

Re: Analogue and Digital callback

The Async interface is there, to support this type of user, but the analogue users come in on the NM-8AM, the ISDN users are the only ones that come in on the BRI. Callback on the analogue is via the NM-8AM, callback for the ISDN user needs to be via the BRI. Will check the URLs though thanks for the advice



Re: Analogue and Digital callback

While there were problems long ago with callback and dialer profiles, they should be fixed in most 12.1 or 12.2 code. Your config looks OK, except that you need to add "dialer remote YYYY" to the dialer profile X so that you can bind correctly. Otherwise, you should check out "debug dialer", "debug 'ppp neg", and "debug isdn q931" (in that order) to try and see what else could be going on. As long as the DP binds correctly, the callback should at least be attempted. Also, don't forget to add "dialer-group" to the DP, too, in addition to an IP address.