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I am having an issue similar to Cisco ASA logs "regular translation creation failed for icmp …" for DNS traffic, yet it works however in my situation the source is a MacBook Pro (10.7) not running BIND.

Every few minutes my ASA logs the following message yet DNS resolution is working fine:

%ASA-3-305006: regular translation creation failed for icmp src inside: dst outside: (type 3, code 3)

Is there anything to be concerned about this message? Is there a way to prevent this message without disabling event 305006 entirely?

share|improve this question is generating an ICMP Port Unreachable message, and trying to send it to

This is essentially the same issue as seen in that other question, while in completely different circumstances; the system (in the case, a DNS client instead of server) gets data that it wasn't waiting for for whatever reason and responds with an Port Unreachable packet.

There's nothing to worry about with regard to functionality as long as your DNS resolution is functioning properly, but getting rid of the logs is a little more iffy. You could potentially have your ASA play DNS forwarder instead of having the client system directly hit the google revolvers.. or just disable the logs.

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