I have an ASA5540 that is in use as a VPN endpoint. I have both LAN to LAN and remote access VPN clients connecting to it. For the past 3 months it will randomly just drop all VPN packets. All other traffic will pass as it is supposed to, but no VPN traffic. I have to completely reload the ASA to revive VPN connectivity.
I was running a code version 7.2.1 but then updated to an interim release 7.2.1 (19) hoping to resolve the issue. No luck. My syslog shows an error message whenever it happens:
CRYPTO: The ASA hardware accelerator encountered an error (Unknown Error, code= 0x3B) while executing the command Process IPSec Outbound Packet (0x11)
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...