Network functions using ppp with null modem cable

Hi everyone.

I’m trying to set up an IBM Director system on two machines both running OpenSuSE 10 using ppp and a null modem cable. The cable is attached to COM1 on both the client and the server.
I’ve initiated ppp using the following commands:

Client command (to be run first)
/usr/sbin/pppd /dev/ttySy connect ‘chat -t 0 RING \c’ debug crtscts local 115200

Server command (to be run afterwards)
/usr/sbin/pppd /dev/ttySx connect ‘chat “” RING\d’ debug crtscts local 115200

These commands run successfully and the two devices can ping each other. If I run ifconfig, I see ppp0 appearing with the correct IP address on both devices.

Now if I try to run any other command over this network, it fails. I am unable to successfully run ssh, scp, telnet or ftp - the result of each attempt is a connection time-out.

Can anyone out there suggest why these commands are not working? I am guessing that I need to add more to the pppd commands above, but I am something of a novice at this protocol. Also, does anyone know if ppp supports transfer of UDP traffic?

Thanks hopefully :slight_smile:


Hi all,

I have realised my mistake. :embarrassed:

The IBM Director feature will not function over ppp unless the linux firewall is disabled in YAST2. I’ve disabled the firewall and my client is successfully discovered.