I have been running a L2TP over IPSEC VPN for awhile now with no problems. For some reason it mysteriously stopped working at 6:45pm CST yesterday. Posted below is the debug log for crypto isakmp and ipsec. Attached is the debug output. 71.40.x.x is the ip address of remote office where the machines remoting in using windows vpn client. 72.5.x.x will equal where the cisco asa 5520 resides.
Will it do LOCAL authenticationby default. I went to double checkand noticed that nder the tunnel-group general attributes there was no authentication methid specified. When I tried to specify it again using the authentication-server-group LOCAL it seems like it will not hold the command.
If you are running Windows and have installed the 07/08 security update ï»¿KB951748 you might uninstall / reinstall the VPN and see if this resolves your problem. I had the same issue happen after the MS update and this fixed it for me.
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...