Am 02.03.2015 um 10:33 schrieb Steffen Kaiser:
hence RBL's make sense in the core because *in front* of any other protocol specific code
That's TCP wrapper or a firewall, IMHO. (for a file list, not RBL). However, there used to be a RBL patch for TCP wrapper and some distribution provide other implementations of a TCP wrapper with RBL
TCP wrapper is dying (more and more software in distributions is built without tcpwrapper support, more and more upstream packages remove support starting with openssh) and given that the author of tcpwrapper is the same person which wrote postfix if it would not make sense in the mail-daemon itself you can be sure it would not be in postfix
one point is logging - frankly i want rejected mail connections in the maillog and not spread over the whole system logs
EADSUP: OpenSSH 6.7 drops tcpwrapper support: https://www.cygwin.com/ml/cygwin/2014-08/msg00345.html