We have a webserver behind an ASA 5520 which has a static NAT setup to forward TCP port 80 traffic through to the private address of the server on port 80 which is working fine.
We are having an issue with one site on the internet being unable to access the webserver properly, and we believe it is due to that particular ISP caching or interfering with port 80 traffic.
In order to test this theory and put in a workaround for this site, we'd like to be able to access this website from another port in additon to port 80 (say 81) without making any changes to the server itself.
Is it possible to have 2 external port numbers (80 and 81) both statically NATing to the same server and internal port?
We would rather keep it working on port 80 for simplicity for most users, but just give this problematic site a different URL using port 81.
Old thread but I happened to run into this and thought I would post just in case someone else ran into the issue.
The only way to configure this is to use a combination of port nat and 1:1 nat. However, the order of the nat is important. If you already have a 1:1 NAT, you must remove it and add the port nat, then add the 1:1 nat back:
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
Table of Contents Introduction:This document describes details on how
NAT-T works. Background: ESP encrypts all critical information,
encapsulating the entire inner TCP/UDP datagram within an ESP header.
ESP is an IP protocol in the same sense that TCP an...