Greylisting has achieved an 85% reduction in SPAM making it to our inbox and quarantine folders - this demonstrates the value of the feature.
However, with 3rd party email servers, I am seeing multi-hour delayed mail delivery, due to server farms sending using different IP addresses.
We are B2B and email delays can represent lost sales... just as email lost in quarantine due to excessive SPAM we have to sort through.
I have been adding domain names to the grelist "whitelist" but am looking for a way to generalize and speed up the process... or even (dare I mention it) be proactive.
My suggestion is allow a wildcard for the domain (for example: *.in.us) to catch all Indiana state email addresses or any other of the multi-domain combinations. It would also be convenient to put in an IP range or subnet to handle some of Google's commercial mail services (or other third party systems).
I have to agree. The delay due to whitelisting being enabled can be horrendous. I know that retries are controlled by the sending server, but it would be great to be able to be proactive and eliminate the unnecessary send/receive mail server chatter.
I have many employees that subscribe to newsletters and other information sources that do not distribute using conventional email servers. Greylisting -- an awesome feature that removes 2/3 of the spam coming to our server -- currently blocks all of these too. Yes, I can survey all our employees and then manually edit a file using NOTEPAD to add each newsletter's sending domain...but that's not very efficient. Wouldn't it be easier if "Greylisting" simply paid attention either to a master Domain list that is more conveniently maintained on the Console -- or better yet, the Allowed Senders lists maintained by each user. If they have a newsletter they like, drag it into their folder!
I agree with this request. Our primary reason for not turning on greylisting, is because of the delays. Anything that can be done to help speed up the management of speeding up greylisting would be greatly appreciated.
I like Doug VanOrnum's suggestion, of an easy to manage master list, to be used in conjunction with recipient's list of allowed senders.