RBL: SpamCannibal is a Honeypot. The only way to get listed on SpamCannibal is for a Mail Server on an IP Address to send their Honeypot unsolicited spam. The problem is when an email account gets compromised (due to an insecure, brute-forced, or stolen password) and sends out spam. It doesn't matter if it is GMail address or a Comcast.net address, everyone who uses that same Mail Server on that IP Address to send email gets flagged by the SpamCannibal RBL.

 

If you use SpamCannibal and are getting a large number false positives I would recommend decreasing the Weight and/or removing the "Enable for Incoming SMTP Blocking" (you would still want to "Enable for Filtering". That way your users will still be able to receive emails flagged by SpamCannibal (they won't be blocked entirely) but depending on the overall weight of the email it may be filtered according to their Spam Filtering actions.

 

Personally we don't use RBL: SpamCannibal on our Mail Servers. I think we were getting 0 hits from it during one of our audits (performed over the course of 14 days) and disabled it because it wasn't an effective means for us (we've disabled 29 RBLs/URIBLs in Smartermail and added 32 others to replace them over the years).

 

Hemen,

 

Our SmarterMail configuration is a bit unique because we have multiple Incoming Gateways and multiple Outgoing Gateways and are very high-volume which prevents us from using many RBLs & URIBLs without paying additional fees for each one. Due to our high-volume of traffic we are forced  to utilize a much smaller number of effective RBLs & URIBLs and skip using many others to prevent from being blocked from overtaxing these free services. As such, our configuration is unusual and complicated, and wouldn't be too useful to anyone unless they are also using separate Incoming & Outgoing Gateways with SmarterMail.

However, Bruce Barnes has published and maintains a stellar document on suggested AntiSpam settings in SmarterMail for those using SmarterMail out of the box on a single server. I cannot recommend it highly enough. It is available for download at https://portal.chicagonettech.com/kb/a171/smartermail-antispam-settings-document.aspx