Can I run a Web server behind a NAT router?

If I have a LAN connected to the Internet via a NAT router and a cable
modem, could I run a computer (running Linux, of course) on the LAN as
a server? If so, how? These routers are supposed to have fancy
firewalls built in to them

_PA

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(E-Mail Removed) wrote:
> If I have a LAN connected to the Internet via a NAT router and a cable
> modem, could I run a computer (running Linux, of course) on the LAN as
> a server? If so, how? These routers are supposed to have fancy
> firewalls built in to them
>
> _PA
>

Hi

You have to setup IP-passthrough. Usually it's somewhere in the
webconfig of your router. Your have to tell it that you want incoming
requests to port 80 redirected to the local ip of your server.

The fancy firewall is principally a NAT box. It masquerades the local
IP's behind your public one. It might have an additional firewall, which
you would have to configure too. But I can't tell... Mine is a Netopia
ADSL router.

Regards
Bram4

- --


BIG BROTHER IS WATCHING YOU
www.anti-dmca.org
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Hi -

On 7 May 2005 16:29:41 -0700, (E-Mail Removed) wrote:

>If I have a LAN connected to the Internet via a NAT router and a cable
>modem, could I run a computer (running Linux, of course) on the LAN as
>a server? If so, how? These routers are supposed to have fancy
>firewalls built in to them

You need to be able to configure the router to forward incoming
connections to port 80 (or whatever port you are going to use) to the
server.

Personally I use a Linux-based system for my router/firewall as well
as my server. A few iptables rules and port 25 (SMTP) and 80 (HTTP)
go to my server. Anything else that is not part of an connection
initiated from the inside gets rejected.

For additional security, the server is in a DMZ, not in the LAN, and
is not permitted to initiate connections to the LAN.

--
Ken
http://www.ke9nr.net/

>>If I have a LAN connected to the Internet via a NAT router and a cable
>>modem, could I run a computer (running Linux, of course) on the LAN as
>>a server? If so, how? These routers are supposed to have fancy
>>firewalls built in to them
>
> You need to be able to configure the router to forward incoming
> connections to port 80 (or whatever port you are going to use) to the
> server.

* One clue: DNAT. Man iptables, of course.

> For additional security, the server is in a DMZ, not in the LAN, and
> is not permitted to initiate connections to the LAN.

* Exactly. If the web-server is in DMZ segment and this is hacked in future
you LAN remains safe.

--
¡Share your knowledge!

Linux user id 332494 # http://counter.li.org/
PGP id 0xC5ABA76A # http://pgp.mit.edu/

Hi ,
This is quite simple
First your ISP must fix you a public adress say "pubaddr1"
then issue this command :
iptables -t nat -A PREROUTING -p tcp -d "pubaddr1" --dport 80 -j DNAT
--to <your server local ip>
Good Luck
S. MAMMAR

(E-Mail Removed) wrote:

> If I have a LAN connected to the Internet via a NAT router and a cable
> modem, could I run a computer (running Linux, of course) on the LAN as
> a server?**If*so,**how?**These*routers*are*supposed*to*have*fancy
> firewalls built in to them
>

You can, if your router supports port forwarding to a specific computer.