network routes

I have a linux box with two internet cards one is connected to a dsl external modem. That card works well.  The second card is connected to a local internet hub.  I can ping the window machines and they can ping the linux box.  Appache setup page will appear on the window machines.  However I can not get through the linux box to the internet.  when I type route I can see both of the cards and status  report is ok.  Ifconfig shows that the cards are up and working.  Why is the firewall keeping the packets from getting to the dsl isp???? Yes I have IPV4 turned on in the /etc/sysconfig/network
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Did you set a default gateway on the windows boxes pointing at the inside interface IP of the Linux box? Is the Linux box configured to route ("FORWARD_IPV4=true" in /etc/sysconfig/network)?
boblantripAuthor Commented:
Edited text of question.
Is IP-masquarding installed? (It's need to be installed in the kernel)

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How about pasting output from ifconfig and route -n here please. You are letting us have to guess at how you set it all up.

Also, if you are using ip_masq, let us know if you are using ipfwadm or ipchains and it would also help if you told us what kernel version you are running as well as which distribution.
echo 1 > /proc/sys/net/ipv4/ip_forward
ipchains -A forward -s -b -J MASQ

Assuming you are using 192.128.0.x as ips on your machines, if not, just update the above.

Or go to and DL pmfirewall, which gives you a pretty decent firewall at the same time. Just answer "yes" when asked for "masquerading?"

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"Assuming you are using 192.128.0.x as ips on your machines, if not, just update the above. "

should of cource be

Assuming you are using 192.168.0.x as ips on your machines on your internal network, if not, just update the above."

sorry for the confusion.
Fixed the -1 problem on this question.
Escrow points corrected.

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Linux Networking

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