ports distributing

Forum: Linux IP NAT Forum
Re: Using Linux NAT like Checkpoint Firewall-1? (Paul Fremantle)
Re: Im doing it
Re: It's work only inside.. (SiFu)
Keywords: Firewall NAT
Date: Mon, 09 Feb 1998 12:02:18 GMT
From: Roberto Favaro <crbild@smc.it>

Hi there, i have one IP address in internet and a Private LAN. I used a Linux like a firewall to this LAN and Internet, but now i would like to use an internal Pc (Win NT) to manage the Mail on the port 25 tcp (SMTP). How can i use NAT to distribute the port 25 only to the NT (forward only this packets) in both way. So i can receive mails and send via NT and inside the LAN i can use POP to connect the clients to the mail server. I tried some configurations but it seems not working. (i have a connection 24h/24h via ppp to an ISP. (of course the sendmail on linux is turned off) the IP address on Internet is 194.243.129.138 (ppp0) and the private Lan is 10.x.x.x the IP on eth0 is 10.1.1.1 and the mail server 10.1.1.100 ipnatadm -I -i -P tcp -D 194.243.129.138/32 25 -N 10.1.1.100/32 25 ipnatadm -O -i -P tcp -S 10.1.1.100/32 25 -M 194.243.129.138/32 25 this seems not work. :( anybody has an answer ? thanks in advance Roberto Favaro

Messages Inline: Outline:

1. tcp port redirection by Michael J. Maravillo, 2/09/98

-> ...should be done using something else by Michael Hasenstein, 2/10/98

-> How to use port forwarding... by Keith, 12/22/98

-> ICQ with IPMASQ by SiFu, 12/22/98

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