We are having an intermittent problem with our remote access VPN to our ASA running the newest IOS and ASDM.
Some users will connect and authenticate to our VPN but then no traffic will be encrypted. Their traffic to the network on the inside of the ASA will be encrypted and sent but nothing will be received (from the counter in the VPN client).
This happens whether the user is local on the ASA or authenticated through Active Directory, it's independent of ASA IOS (we've been through 2 versions with the same issue), VPN client version (tried 4.x, 5.x) and independent of the Clients OS.
The strange part is I can not replicate the issue on my PC consistently. I have tried every version of the VPN client and Windows XP, Vista, and 7 with no issues. The only time I had issues was connecting with Vista then disconnecting and connecting with XP a few seconds later. This only happened a hand full of times though.
Has anyone experienced anything like this before or can point me in a new direction?
We have experienced that problem also, if a single user will connect to our ASA5510 using VPN it can receive traffic. But if more that 1 user will connect using the same Public IP they can't receive any traffic. The problem was about NAT in IPSec so someone pointed me to issue this command: crypto isakmp nat-traversal 10, an it solved my issue.
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...