See this and the Procedure section if your IP address changes everytime you connect to the internet.
Thanks to Peter Illmayer for the following submission to me: (This will work out best for those of you with dynamic IP's...)
------------------------------------------------------------
IN debian, I created a forward file in /etc/ppp/ip-up.d and put in
#!/bin/sh
ppp_ip="`/sbin/ifconfig ppp0 | grep 'inet addr' | awk '{print $2}' | sed -e
's/.*://'`"
/usr/sbin/ipmasqadm portfw -f
/usr/sbin/ipmasqadm portfw -a -P tcp -L ${ppp_ip} 6702 -R 192.168.0.2 6702
This is in a 2.2.x kernel with ipmasqadm installed with the appropriate
kernel modules compiled in.
---------------------------------------------------------------
Charles J. Fisher pointed out that a similar script can be used
if you are using DHCP, insert the following lines in a script that runs after you get your IP address.
net_ip="`ifconfig eth0 | awk '/inet/ {sub(/addr:/,"",$2); print $2}'`"
/usr/sbin/ipmasqadm portfw -f
/usr/sbin/ipmasqadm portfw -a -P tcp -L ${net_ip} 6702 -R 192.168.1.2 6702
Of course the more machines using Napster behind your IPMasq'd machine the more port forwards you need to do.