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Step-by-Step Configuration and Troubleshooting Best Practices for the NGFW, NGIPS and AMP Technologies A Visual Guide to the Cisco Firepower Threat Defense (FTD)
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PTR RECORDS and static translations

Hi. I am certain the issue we are experiencing is one that is very common. We have an internal spam filter [] that receives all smtp traffic by being translated to [obviously an example IP] on the Internet. Therefore, our public is Now, our mail server [] send OUT mail on [public]. The PROBLEM is that today, many firms are using reverse lookups when they receive an email. Thus, an email received from us has a source address yet our 'SPF' record returns for the lookup. The mail is droppeed. We need to have all smtp outbound mail 'look like' its source address is EVEN THOUGH incoming traffic for goes to the spam filter at I hope that makes sense.... I've tried reversing the parameters in static translations to now avail... Please help.


Community Member

Re: PTR RECORDS and static translations

Did you ever get this resolved? If so can you share the fix?

Community Member

Re: PTR RECORDS and static translations

Yes sir.

The solution was to have the firm we were speaking to point to a 2nd IP as a 2nd PTR and then we xlated the spam filter to IT, and we were OK. A band-aid, but it worked! :) I hope this helps you!!

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