Gateway Configuration

JustJD · 07-19-2005, 03:02 PM

How do I edit the iptable? I have two Interfaces on the gateway - one that is connected to the Internet and one that is connected to the hub. The clients are also connected to the hub. I want the clients to make requests via the gateway - how do I set up IP Masquerade?

win32sux · 07-19-2005, 03:22 PM

if eth0 is facing the Internet and eth1 is facing the LAN, then this would do it:

Code:

iptables -P FORWARD DROP

iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT

iptables -A FORWARD -i eth1 -o eth0 -m state --state NEW -j ACCEPT

iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

make sure you have forwarding enabled:

Code:

echo "1" > /proc/sys/net/ipv4/ip_forward

just my

...

JustJD · 07-21-2005, 03:39 PM

Thanks for the info - followed your instructions but I still no joy. eth0 is connected to the Internet - fine- when I try to enable eth1 I get the message "Determining IP information for eth1...." then nothing?

win32sux · 07-21-2005, 04:04 PM

Quote:

Originally posted by JustJD
Thanks for the info - followed your instructions but I still no joy. eth0 is connected to the Internet - fine- when I try to enable eth1 I get the message "Determining IP information for eth1...." then nothing?

well, my post assumed your interfaces were already configured...

sounds like your eth1 is trying to find a DHCP server... perhaps you should instead assign it a static ip address like 192.168.0.1 on subnet 255.255.255.0 for example??

JustJD · 07-21-2005, 04:31 PM

If eth1 is connecting to the hub using the static IP address 192.168.0.1 will it then be listening for traffic? What address do the other clients use to request a connection from the gateway to the Internet?
Say: ifconfig says that the address of one client connected to the hub is 192.168.0.104, the next is 192.168.0.103, and the static address I assigned to gateway is 192.168.0.1, which is connect to the uplink jack of the hub.

Do the clients make requests to 192.168.0.1?

win32sux · 07-21-2005, 05:30 PM

yes, the clients would need to have 192.168.0.1 configured as their gateway...

<Ol>Origy · 07-22-2005, 01:47 AM

Also don't forget to provide the clients with the proper DNS server IPs (your ISP).
This will allow them to access websites by name e.g. www.google.com instead of 66.249.85.104

~Ol