If you are running pix 6.2 or higher, run a two sets of capture commands, one on the inside interface and one on the outside interface. Have a customer that is having trouble connecting to try again while running the traces. Then save them, and re-run them again, but this time, have a customer that is working try to connect.
Then compare the good and bad traces to see what is different.
According to the pix 6.2 and 6.3 doc the tcp reset-i is orginating from the terminal server (port 3389). I wonder if the reset occurs because it is expecting a frame from the user within one second of est. the connection. The good vs. bad compare will verify this.
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...