My box runs Devuan Beowulf and within it runs a (VBox) Devuan ascii virtual machine set up
to start up automatically when I boot.
It is not kept on 24/07 but is booted up a few times every 24 hours.
The Devuan ascii virtual machine runs PI-Hole as a recursive DNS server.
It is all working as it should but there's a 'snag in the weave' so to speak:
When booting, I'm getting a (not too) short delay at "Starting MTA:" which is when (as I
understand it) Exim4 does a reverse DNS check.
The problem is that my DNS (unbound) runs on the Devuan ascii virtual machine which I set
up to start up automatically at boot but it is not yet up and running when Exim4 does the
reverse DNS check.
Hence the delay (30/40s?) I am refering to.
Exim4 is set up to receive "local delivery only; not on a network", listens only to IP 127.0.0.1
for incoming SMTP connections and accepts my box's user as the only other destination for
which mail is accepted.
As I am on a wired ADSL connection and have "always on" web access, "Dial-on-Demand"
configuration is disabled.
Is there a way I can avoid the "Starting MTA:" delay at boot?