I don't want to enable it because I don't want ICMP to pass through the firewall, i.e. I don't want anyone to be able to ping or traceroute the firewall, at all. Is this sys log ID something that I should be worried about?
If you don't want ICMP to be passing through the firewall, then no you don't have worry about these messages. They are simply indicating that the firewall is doing its job correctly.
As the syslog documentation says, you can block ICMP on your inbound ACLs and this will prevent the firewall from processing the packets and generating these messages (though you may then see messages indicating the traffic was dropped to an ACL rule depending on your logging level).
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...