Topic: Adding outgoing email recipients to the whitelist

[mrkiwi]

Hi All,

I've searched the forum but not found an answer to this, maybe because it's a bad idea?

I have a number of customers with SME servers, all having a non-zero number of problems each month with incoming email from legit sources being bounced back.
Some of it was the SORBS.net problem, but others are due to the sender being blacklisted for a very short period of time. Even authsmtp.com gets blacklisted from time to time i have found.

What im looking for is a plugin to take addresses from outgoing email and add them to the whitelist - so by default if you sent mail to x@y.com (via SMEServer), they should have no problem sending email back to you.

Can anyone point out the pitfalls?

1. If you send email to a spammer, they are whitelisted. (Well - that happens so infrequently, and the spammers sender address is so often thrown away that i dont think the number of occurances of this are worth worrying about. Also you can manually remove someones address from the whitelist if this happens)
2. The whitelist could get huge. ( Yes, but wouldnt the reduction in scanning/processing time for incoming email [ie if you get a hit on the whitelist you can avoid all the expensive? RBL lookups] mitigate this somewhat? Is the whitelist a hash table? Is this expensive to edit/add to? )
3. This will only be worth doing if the SMEServer is the bridgehead. If your ISP accepts your email and you pop it from there or use fetchmail, this may not help you.

[janet]

mrkiwi

The starting point here is that a default SME does not reject spam. The admin user enables spam filtering, anti virus filtering and RBL rejection during the initial setup.

Implicit in this is that your RBL rejection problems come from using RBL lists that are too aggressive.
I suggest you remove some lists, use the "conservative" lists as per FAQ here
http://wiki.contribs.org/SME_Server:Documentation:FAQ#Real-time_Blackhole_List_.28RBL.29

I have a number of customers with SME servers, all having a non-zero number of problems each month with incoming email from legit sources being bounced back.

What you want has already been invented. The system answer to this is to enable greylisting (& disable RBLs as necessary).
Some people say greylisting works great for them, others do not recommend using it due to various technical issues with external mail server misbehaviour.
It seems to suit situations very well that have a stable group of email contacts.
Search these forums for a number of good posts on the topic, and some specific qpsmtpd plugin configurations steps.
eg this post (but there are others)
http://forums.contribs.org/index.php/topic,44032.msg215275.html#msg215275
and this
http://forums.contribs.org/index.php/topic,33662.msg153187.html#msg153187