No subject

own networks (incl. 10/8 etc private ranges), so that
your own network will not depend on various blacklists.

But this is done differently.

Don't QUERY a dnsbl for hosts inside your network ranges.
F.e. your dnsbl server may be down for any reason (eg, a
dnsbl you download does not work and gave invalid data,
rbldnsd refused to load it and hence returns SERVFAIL to
all queries, or the like), but your LOCAL mail should
still be flowing regardless.

Another variant is to split inbound and outbound mail
servers, so you don't have to exclude your ranges at
all, and it makes other things easier.

/mjt