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New Member

Blacklist Proactive Solution

Good day folks,

Our IP address was recently blacklisted due to a misconfiguration/hack on our IronPort. This hole has been addressed.

I am seeking advice on how to reduce the impact on our business when we are blacklisted. It seems common that BLs take 24-48 hours if not longer to clear up. This cannot fly in a business environment.  How do you have your infrastructure setup to reduce the impact of a BL?  Do you have multiple IP addresses configured for SMTP traffic?

We have a single Cisco ASA firewall and all outbound mail traffic (SMTP 25) goes through the device. A reverse lookup currently shows our ASA's IP address.

My theory is to configure a second external IP address in order to move SMTP traffic through while we are on a blacklist.

Thanks for any advice.



Blacklist Proactive Solution


did you request to add a reverse PTR for your mail server at ISP level?

New Member

Blacklist Proactive Solution

At this point, no. I am just looking for suggestions and what to do (or what not to do).  In combination to my theory, that does seem logical. Thanks!

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