On Mon, Aug 10, 2020 at 07:47:35PM -0400, Adrian Pepper wrote:
> However, /usr/lib/sendmail would appear to work fine to
> send outgoing mail. Headers seem to suggest that messages
> do get queued without using an smtp connection at all.
Yes, local mail submission does not require an SMTP server.
> I can't find an "official" way to listen on no inet_interfaces.
master_service_disable = inet
you can also simply remove all "inet" services from master.cf. This
assumes no SMTP content filters are involved in handling outbound mail.
> Or, will, under some circumstances, the actual loopback interface
> be required, e.g. in backlog situations?
No.
--
Viktor.
