Good Day! I have a firewall having two NICs. My configuration:
domain - mydomain.com eth0 - facing the internet eth1 - secured network (say, 192.168.1.1) I'm planning to forward all mails using mydomain.com into my virtual mail server (say, 192.168.1.2). Obviously I made use of ports 25 (SMTP) and 110 (pop3) here. I did something like: #iptables -t nat -A PREROUTING -p tcp --dport 25 -i eth0 -j DNAT --to 192.168.1.2:25 #iptables -A FORWARD -p TCP -d 192.168.1.2 --dport 25 -s 0.0.0.0/0 -j ACCEPT #iptables -t nat -A PREROUTING -p tcp --dport 110 -i eth0 -j DNAT --to 192.168.1.2:110 #iptables -A FORWARD -p TCP -d 192.168.1.2 --dport 110 -s 0.0.0.0/0 -j ACCEPT #iptables-save > /etc/sysconfig/iptables when i do "iptables -t nat -L" it says: Chain PREROUTING (policy ACCEPT) target prot opt source destination DNAT tcp -- anywhere anywhere tcp dpt:smtp to:192.168.1.2:25 DNAT tcp -- anywhere anywhere tcp dpt:pop3 to:192.168.1.2:110 Chain POSTROUTING (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination "iptables -L" it says: Chain INPUT (policy ACCEPT) target prot opt source destination Chain FORWARD (policy ACCEPT) target prot opt source destination ACCEPT tcp -- anywhere 192.168.1.2 tcp dpt:smtp ACCEPT tcp -- anywhere 192.168.1.2 tcp dpt:pop3 Chain OUTPUT (policy ACCEPT) target prot opt source destination I test thru telnetting from remote computer: #telnet <eth0's ip add> 25 Trying xxx.xxx.xxx.xxx... In here it seems like i can't connect using ports 25 and 110. When i try to use nmap to determine ports 25 and 110 are open: #nmap xxx.xxx.xxx.xxx it says: 25/tcp filtered smtp 110/tcp filtered pop-3 I figure out that my forwarding doesn't seem to work at all. Did I miss something here? What seems to be the problem? Please help!!! Thanks, Oliver _ Philippine Linux Users Group. Web site and archives at http://plug.linux.org.ph To leave: send "unsubscribe" in the body to [EMAIL PROTECTED] Fully Searchable Archives With Friendly Web Interface at http://marc.free.net.ph To subscribe to the Linux Newbies' List: send "subscribe" in the body to [EMAIL PROTECTED]
