I am not sure what's going on, but I have setup a gateway debian box with iptables and dhcpd server. The server is handing out the ip addresses to the clients just fine, gateway being set to the debian box and dns set to the ISP dns. Now I can't figure out why the net isn't working on the clients computers. The box is configured as eth0 (192.168.0.1) being the internal LAN and eth1 being the external to the internet. I have ip_forwarding set to 1, on as well. Here is my output from the iptables-save command. If anyone can help, please let me know!
UPDATE 1: I redid the rules to very very basic and it still is happening... tracert times out on the client and can't ping google on the client but can ping the gateway and other clients...and NET works fine on router box
UPDATE 2: As per Patricks suggestion, set forward to accept and still having same issues.
# Generated by iptables-save v1.4.8 on Mon Mar 5 20:46:23 2012
*mangle
:PREROUTING ACCEPT [8:608]
:INPUT ACCEPT [8:608]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [4:528]
:POSTROUTING ACCEPT [4:528]
COMMIT
# Completed on Mon Mar 5 20:46:23 2012
# Generated by iptables-save v1.4.8 on Mon Mar 5 20:46:23 2012
*nat
:PREROUTING ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
-A POSTROUTING -o eth1 -j MASQUERADE
COMMIT
# Completed on Mon Mar 5 20:46:23 2012
# Generated by iptables-save v1.4.8 on Mon Mar 5 20:46:23 2012
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [5:628]
-A INPUT -i lo -j ACCEPT
-A INPUT -i eth0 -j ACCEPT
-A INPUT -i eth1 -p tcp -m tcp --dport 22 -j ACCEPT
-A FORWARD -s 192.168.0.0/24 -i eth0 -j ACCEPT
-A FORWARD -d 192.168.0.0/24 -i eth1 -j ACCEPT
COMMIT
# Completed on Mon Mar 5 20:46:23 2012
You have the
FORWARDfilter set toDROP. So iptables is dropping all forwarding. If you want to keep it set toDROP, you need to add the following rule