We're upgrading our network. As a part of the process we're replacing our 1750 Routers with a ASA 5505 with the latest software version 8.0.4.
As far as ACLs, NAT'ing and routing goes so the config is the same on the new box.
The problem is with a remote PC we have on the other end of a point to point SHDSL connection. The connection is VLAN, layer2 based and there are no routers in between, just a modem at each end.
what happens is that traffic is dropped on the inside interface of the ASA box from the remote PC. Traffic from the ASA to the remote PC (ping for example) is fine, also the remote PC can ping other IP addresses at the other end of the DSL line but not the inside IP of the ASA.
It makes no difference if the link from the remote site is connected directly to an ASA port or via another switch.
We've discovered that if we clear the ARP cache of the remote PC we get 1 ping reply before traffic is dropped.
Pinging the remote site from the ASA works though we experience a certain amount of lost packets.
There's something about the ASA and this type of link that's causing this but we don't know what. Our best guess is that it's some kind of security feature ??
Put in a PC with the same inside IP, mac address as the ASA, cable etc. and traffic flows both ways without a problem which is why we think it's down to the ASA.
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...