Cisco 1700 routers AUX port Modem question.

[Challenger]

Hi all,
We have several 1700 series routers out in small branches and seem to be having problems with a few on the modem connection via the AUX port. Sometimes it will connect but not go through to the router prompt,
CONNECT 31200

So even if you hit enter a few times, it just sits there, call stays connected but no router prompt, we've tried different cables and known working modems and still have the problem, has anyone else struck this or know a resolution ?
Thanks,
Steve.

 

[eurobadger]

Hi Steve

Is your AUX port still set with hardware flow control (this is default) and does your modem also have hardware flow control enbled?. If these do no match the modem will report 'connected' because that is a function of the modem, but the data will not be passed.

Also which modem are you using? I had particular problems doing this with Zyxel modems, because they use a modified Hays command set, and I struggled to get the right command sequence to set up the flow control.

EB

 

[Challenger]

Thanks EB,
Here's most of what's in the conf for the aux port:
autobaud
login
modem Dialin
transport input all
flowcontrol hardware

The thing is, the modem will work when we test it on routers with us, it is of course only when we send it out that it mis-behaves !
We use mostly Dataplex DPX series modems. Are you talking AT&K or s reg for the flow control ?
Thanks for the reply !
Steve.

 

[vipergg]

Also you should hardcode the modem speed to 9600 if possible , the ports will only transfer at that speed by default .

 

[eurobadger]

Steve

We use AT&K. Also vipergg makes a sound point.

The routers I was working with were for a client in the Middle East. We had frequent issues with the phone lines, with the quality being so poor that the modem spent its time sorting out the retries, and trying to handle the PSTN side of it that 'connect' was often the only activity we got. Identical setups in Europe and Central America were fine, as were tests in house.

Final issueerformance was poor while using a desktop PC with an inbuilt modem, and the whole thing worked much more successfully using an external modem to do the dialling to the remote site.

Hope this helps....

EB

 

[Challenger]

Hi,
Thanks for the replies, we finally discovered that the modems have 2 ports one marked line and one marked phone, when installed by the staff in the small branches, some chose phone ! We need to tape over so they can only use line !!!
Steve.