Kurt:

> Hello all. Hate to say it but I am fairly new to Linux. I have been
> studying Unix for about eight months now in college and have loved every
> minute of it. So I decided to leave M$ behind and just installed
> Mandrake 8.2. I love the system but have one major problem at the
> moment. 

> I have a 128K dual channel ISDN line and I have an Adtran Express 3000
> external modem. The problem is that I can hook up with one channel just
> fine, but I cannot seem to hook up with both channels to get the full
> 128k of bandwidth (that I have to pay dearly for due to my location).
> Right now I am using kppp as my dialer (could this be the problem?)

I assume that you have verified that this configuration (bonding both
channels) works OK in Windows, and that your ISP continues to allow
you to use both ports.

The only ISDN modems I've messed with in Linux have been Motorola Bitsurfr 
Pros (in a pair, so I used Motorola's proprietary inverse multiplexing to 
bond both channels together) and the 3Com ISDN TA and the 3Com 3C882 ISDN 
modems.

The 3Com modems worked OK with every ISP I tried (including UUNet) with
both channels.

On both of the 3Com modems the following dial string is necessary to
bring up both channels:

chat -v ABORT BUSY ABORT "NO CARRIER" "" 'ATDT3033810136\&3033810136' CONNECT || exit 1

That is from my /etc/ppp/ppp-login script that actually dials the modem
and brings up the serial link before PPP starts.  There is also an AT
command string required to enable both links, which for 3Com is:

/usr/local/bin/chat -v "" ATZ OK ATS0=0*VI=5*VO=5*PPP=3*A0=0*B=0*K=1*E=0 OK "" || exit 1

You should look in the manual for your ISDN modem to see what the init
string and dial string are for your modem to enable both channels.  The
Windows software that runs the modem issues those commands in the back-
ground so you never see them.

Hope this helps.

--
Jim Ockers (ockers@ockers.net)
Contact info: please see http://www.ockers.net/

Fight Spam! Join CAUCE (Coalition Against Unsolicited Commercial Email)
at http://www.cauce.org/ .