Solved

Cisco ASA VPN Nat Problem

Posted on 2010-11-21
9
881 Views
Last Modified: 2012-06-21
I have an ASA 5500 connected to the internet. I have a remote site with a cisco 877 connected to the ASA over a l2l VPN over the internet.

I want to make one of the hosts at the remote site available to the public internet so I assume I need to use a static NAT on the firewall.

I am a little confused about how to do this.

Essentially, the traffic will come in from the internet to the outside interface and then be natted, encrypted and sent back out the outside interface over the VPN to the host.

How do I do this as they are both on the outside interface?

static (outside,outside) public address internal adress?

0
Comment
Question by:question01
  • 2
  • 2
  • 2
  • +3
9 Comments
 
LVL 3

Expert Comment

by:caballo_oscuro
Comment Utility
use an extnded access control list that prevents (deny) the exact network from gaining access to the 80 port of the router then permit the other network any any. Place the acccess control list on the appropriate port on the router.
0
 
LVL 2

Expert Comment

by:ksaiki
Comment Utility
Is your network topology like

internet -> cisco 877 --nat--> host

?

Why is VPN involved?

0
 
LVL 4

Accepted Solution

by:
ullas_unni earned 500 total points
Comment Utility
yea that static should do the trick... but make sure u have the command 'same-security-traffic permit intra-interface' in place.

u can even do a nat:

nat (outside) 1 <internal ip> outside
global (outside) 1 interface  ---- (which i assume u will be having)

so that u pat the internal ip to the outside interface of the ASA saving the public ip u are using for the static nat.
0
 
LVL 29

Expert Comment

by:Alan Huseyin Kayahan
Comment Utility
Unless the whole traffic of the host at remote site that you want to make public, tunneled to ASA, including the internet traffic, what you want to do is not possible.
0
What Is Threat Intelligence?

Threat intelligence is often discussed, but rarely understood. Starting with a precise definition, along with clear business goals, is essential.

 
LVL 33

Expert Comment

by:MikeKane
Comment Utility
Also,  why would you want traffic to come into the ASA then sent back out the interface to the remote site?   Wouldn't it be easier just to have the traffic directed over there?  

Do you want traffic to come into the ASA then sent across VPN to the other site's host?  
0
 
LVL 1

Author Comment

by:question01
Comment Utility
Good question MikeKane.

(Remote Site) cisco 877 -------------- Internet------------------ ASA

With a VPN betwen the 877 and the ASA.
At the moment all traffic from the remote site comes back to the main site (ASA) over the VPN before being sent back out the same interface to the internet. There are a few reasons for this, proxies etc...

I want a host (Video conferencing unit) on the remote site to be publically accessible from the internet. The only spare IP address space we have is on the network that connects to the ASA so I was planning on using one of these addresses as the public address for the host at the remote site.

 
0
 
LVL 29

Expert Comment

by:Alan Huseyin Kayahan
Comment Utility
So remote site goes to intervet via ASA's internet connection. For a simple test, tell a user at remote site to enter www.whatismyip.com . If it is the same with the one that a user at HQ behind ASA sees at the same web address, then the outside,outside static should work.
0
 
LVL 2

Expert Comment

by:ksaiki
Comment Utility
internet -> (public IP)ASA -> NAT-dst -> routing lookup -> VPN Tunnel -> 877 -> Video Conf

like this?




 
0
 
LVL 1

Author Closing Comment

by:question01
Comment Utility
tested solution and worked well.
0

Featured Post

Highfive Gives IT Their Time Back

Highfive is so simple that setting up every meeting room takes just minutes and every employee will be able to start or join a call from any room with ease. Never be called into a meeting just to get it started again. This is how video conferencing should work!

Join & Write a Comment

Like many others, when I created a Windows 2008 RRAS VPN server, I connected via PPTP, and still do, but there are problems that can arise from solely using PPTP.  One particular problem was that the CFO of the company used a Virgin Broadband Wirele…
From Cisco ASA version 8.3, the Network Address Translation (NAT) configuration has been completely redesigned and it may be helpful to have the syntax configuration for both at a glance. You may as well want to read official Cisco published AS…
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…

763 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

11 Experts available now in Live!

Get 1:1 Help Now