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blocking criteria sequence - why is RBL before IP and Reverse DNS blocking?

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#1 Forrest Mook

Forrest Mook
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Posted 13 December 2018 - 10:49 AM

On my Barracuda Email Security Gateway I am making extensive use of blocking based on reverse DNS entry, and IP address allocations.  This works great.   However, I notice in my message log that many messages have a reason for being blocked of "External Blacklist" or "Barracuda Reputation Blacklist" even though the source IP address would have been blocked based on my reverse DNS blocking or IP address blocking.......


My question is, why isn't the Email Security Gateway programmed to block the message based on reverse DNS rules or IP addresses as the first check?    I assume this is generating unnecessary queries toward the various RBLs.   Assuming this is how it works, can someone from Barracuda submit this as a change request for a future firmware update to put IP address and reverse DNS checking ahead of RBL checking to cut down on unnecessary RBL queries?  Thanks