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Old 11-08-2005, 09:20 AM   #1
rubella
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Registered: Sep 2005
Location: Europe
Distribution: debian sarge
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iptables - servers not accessible from lan using external ip


hey

I have an internal network connected to the web through a debian box with iptables. All clients can connect to the internet using NAT.
On the same lan, i have some servers i can reach with their internal ip-address. I assigned fixed external ip's to these servers and from outside it's possible to connect to them. When i try to connect from inside the lan to this servers using their external ip, i won't work... timeouts... but i need those fixed addresses for DNS-entries, so i can connect the server from inside using an url.

anyone an idea where i'm going wrong? thx!
 
Old 11-08-2005, 08:20 PM   #2
Brian1
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Registered: Jan 2003
Location: Seymour, Indiana
Distribution: Distribution: RHEL 5 with Pieces of this and that. Kernel 2.6.23.1, KDE 3.5.8 and KDE 4.0 beta, Plu
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If I understand you have a dns server setup so outside address can be routed. If this is the case I would leave that dns server the way it is and setup a second dns server for internal use. If you modify one then you will need to modify the other manually. The only way I got around this in the past.

Brian1
 
Old 11-08-2005, 08:40 PM   #3
Capt_Caveman
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The local DNAT problem.

You can also use iptables to solve this if DNS isn't an option. Here are two explanations of the problem and solutions:
http://www.netfilter.org/documentati...-HOWTO-10.html
http://iptables-tutorial.frozentux.n...tml#DNATTARGET
 
Old 11-09-2005, 03:39 AM   #4
rubella
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Brian & Capt Caveman, great job dudes! thx!
 
Old 11-09-2005, 06:08 PM   #5
Brian1
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Great links ther Capt Caveman. Never thought about postrouting in that way. That sure beats maintaing 2 seperate configured DNS. A quick read over the second link had an idea I never thought about doing either. I will bookmark those and readup on them.

Thanks for the links. Glad to be of help.
Brian1
 
Old 11-09-2005, 07:03 PM   #6
Capt_Caveman
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No problem. I had the same problem when iptables first came out and had a hell of a time diagnosing the problem (this was before those docs were available), so I can certainly relate to how frustrating it can be.
 
Old 12-12-2005, 09:16 PM   #7
MarleyGPN
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sorry wrong thread

Last edited by MarleyGPN; 12-12-2005 at 09:18 PM.
 
  


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