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Problem publishing servers with ISA and Cisco ASA 5520

Last Modified: 2013-11-16
The configuration that I want to use is to have our Cisco ASA 5520 filtering traffic from the Internet and our DMZ and the ISA server will sit behind that connected to our internal network.  The problem that I have is we need to publish several servers using different public IPs statically NATd throught the ISA.  The Cisco ASA will only allow me to map 1 public IP to the outside interface on the ISA server.  But I need to have 4 different IP statically NATs to the ISA for the servers.  Moving the servers into the DMZ or in front of the ISA are not an option today.
Watch Question

you should be able to set up static one-to-one NAT commands on the ASA.

the command will be similar to this;

static (DMZ,outside) tcp web web netmask
WH_TechIT Manager


Yes. The problem I am having though is that the ASA will only allow me to map one public IP to the outside interface of the ISA server.  If I try to add a second static mapping to the ISA interface, I get an error about overlapping IP mappings.

or without PAT the command looks like this:

static (DMZ,outside) netmask

where is the ip address of the DMZ server

and is the IP address you want the firewall to give the DMZ server

what is the subnet mask you have assigned to the outside interface of the ASA?

"I get an error about overlapping IP mappings"

that means your other NAT commands are already performing NAT for those IP addresses.  Do you have some other NAT commands for traffic going from DMZ to outside?
WH_TechIT Manager


Maybe this will  help clairify what I am trying to do:

We currently have a Cisco ASA5520 and I want to use ISA Server 2006 for a web proxy/caching and to publish some of our internal servers.  Can the two of these be configured to work in tandem?  The servers are statically mapped to separate public IPs on the Cisco ASA.  Can ISA 2006 publish server mapped to separate Public IPs.  The Cisco ASA will not let me map several different Public IPs to the same private IP, like the outside interface of the ISA server.
Here is a rough example of our layout:
Internet----Router----Cisco ASA----ISA Server----Private LAN
                                         |                                                |
                                     DMZ                               Servers to be published

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