which one is executed first ip_forward=1 or iptables FORWARD Drop

[BELAHCENE Abdelkader <abdelkader.belahcene@enst.dz>]

Hi,

I am using  one machine, say SERV,  as a gateway ( cards eth0, eth1) from network1  to network2, I want to forward  all packets but tcp port 80   so I used  

sysctl -w net.ipv4.ip_forward=1

I want to drop port 80, and accept others port

I tryed

 

iptables -A FORWARD -i eth1 -o eth0 -p tcp  --dport 80 -j DROP

but not ran

Thanks for help

regards