On Mon, 8 Nov 2021, JHM via Exim-users wrote:
> Hello:
>
> 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?
Well, this is the sort of problem systemd is supposed to avoid :-)
As Evgeniy said, you can do things with the init files to work around
the problem.
Alternatively you could arrange that exim is started by inetd
(perhaps rlinetd or xinetd these days) each time there is a connection,
rather that running as a daemon.
--
Andrew C. Aitchison Kendal, UK
andrew@???