Re: [exim] Exim4 delay at boot

> > 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.

> Well, this is the sort of problem systemd is supposed to avoid :-)

In case the queries cannot be served from local zones, even if the name
server is up, it may be unable to answer the query successfully if its
peers or the network to them is down.

This is a typical problem with many Unix applications: If DNS was down
while the system started, things fail in weird ways. Resolving the
service dependencies only solves the common case.

In the old days, people put queries to be resolved while booting in a
hosts map. I always recommend to check a system by starting it without
network connection to see what happens.

Michael