I'm upgrading from 8.8.8 to 8.9.0 and I've been looking for the
answer to the following questions...
What is the format for /etc/mail/relay-domains?
Is this only for domains or can individual machines be listed?
Can I list IP addresses or ranges of IP addresses?
Or should I be using /etc/mail/access for this?
I'd like to allow relaying for a handful of machines and deny all
(If this is in a FAQ somewhere, please point me to it.)