Leigh S. Jones, KR6X wrote:
kr...@kr6x.com wrote:
No one has mentioned that it's necessary to wait until
the possible spammer identifies his target to know
whether the target has him whitelisted.
Gordan wrote:
Whitelists aren't really practicaly on big setups. You need to block a
lot before they even get as far as talking TCP. If you can manage a
decent job with that, RBLs can prune enough of what's left for
spamassassin and virus scanners to be able to cope with the minute
amount of mail that is actually deliverable. It is not all that uncommon
to see the spam:ham ratio of around 250:1. When you have a system
handling mail for half a million domains, well, you get the idea.
Whitelists aren't really practicaly on big setups handling mail for half
a million domains. Ahhh, but nonetheless they are a part of the
Courier algorithm...
I'm not saying the idea is bad. I am saying that when your server is
receiving the best part of a million emails per hour, most of which is
spam, you cannot necessarily afford to pick up the connection, see who
it's for, check the white list for the recipient if they are valid, and
the selectively let the mail through to be processed by, e.g. content
based scanning for spam and virii, and then maybe deliver it to the
final destination. There are good ways of separating wheat from the
chaff without incurring any false positives before you ever pick up a
TCP connection. But this is rapidly becoming a conversation OT for this
list...
Gordan
9 messages in net.sourceforge.lists.courier-usersRe: [courier-users] RBL Check - When?
