Using RBL+ with Exim
The main guide "The MAPS RBL+ in JANET" points out that RBL+ combines three MAPS lists which JANET users may wish to use separately. This short note outlines a way to distinguish between the three lists using recent versions of the Exim mail server product.
The matches in the rbl_domains parameter can be refined by listing the returned addresses that each will recognise.
For example, if this old-style Exim setting for the separate DNS zones of:
rbl_domains = blackholes.mail-abuse.org/reject : \
dialups.mail-abuse.org/warn : \
relays.mail-abuse.org/warn
is replaced by:
deny dnslists = \
rbl-plus.mail-abuse.ja.net=127.1.0.1,127.1.0.3,127.1.0.5,127.1.0.7
warn dnslists = \
rbl-plus.mail-abuse.ja.net=127.1.0.2,127.1.0.4,127.1.0.6
the effect will be logically identical.
By choosing the lists in each line carefully, entering them in the right order and including the right keyword (deny or warn), it should be possible to reject connections from any combination of lists and add warnings for messages received from addresses on others.
The above configuration is believed to work with current releases of Exim (version 4).