hi world, I have a Redhat linux firewall 7.2, with 2 network interface. a public and a local. I have a microsoft Exchange server in my local network. How i need to config my firewal and MS Exchange to reseive emails from outside with my public domaine. Tanks for your help ! Sylver

Greetings: I've some problems like that. I configured SuSE 7.3 (kernel 2.4.0) as proxy and I try use the iptables and sendmail for connect a internal MSExchange Server with the world, but dont works!!! What rules I need to install using iptables for make it works only NAT service!!! Carlos

Hi, to Enable packet forwarding. To do this at system boot, make sure the file /etc/sysctl.conf contains the line net.ipv4.ip_forward = 1. and use the ipchains command : ipchain -A forward -s local_net -d 0/0(anywhere) -j MASQ exemple: ipchains -A forward -s 192.168.0.0/24 -d 0/0 -j MASQ To enable packet forwarding without rebooting, as root issue this command or reboot: echo 1 > /proc/sys/net/ipv4/ip_forward Now you are able to do the NAT with your local network. you can go at this URL: http://www.redhat.com/docs/manuals/haserver/RHHAS-1.0-Manual/x4011.html Sylver B.