I'm having an issue trying to open port 25 on our cisco ASA 5510 version 9.1 (2). When a wire tap is placed on the outside port between the ASA and the internet we are getting hits on wireshark, when a port 25 trace from http://www.yougetsignal.com/tools/open-ports is run. No hits or activity is showing up on the debug log using ASDM, even when filtering is applied.
Problem is we cannot open port 25 traffic from the outside network to the inside network so that smtp mail can flow to the Exchange server *.102. Mail can go from the inside network to the ouside network and out to the internet no problems (internal being the most trusted obviously).
Please find attatched the config for the ASA. I have replaced the companyname/domain with "ourcompanyname", our public IP to "ourpublicIP", our ISP to OurISP and our internal IP's with *.*.*.* for sanitisation reasons.
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...