Ranjan Maitra:
> On Wed, 25 Mar 2020 10:31:11 -0400 (EDT) Wietse Venema <wie...@porcupine.org>
> wrote:
>
> > Ranjan Maitra:
> > > So, I have tried to set the relayhost to a specific mailhub address but
> > > have not been able to make this work. I get a message then which reads
> > > like:
> > >
> > > delivery temporarily suspended: lost connection with the mailhub server
> > > while receiving the initial server greeting
> >
> > This is exactly what you need.
> >
> > Postfix will keep trying until the VPN comes up.
> > To expedite deliveries then you would say "sendmail -q" after the VPN is up,
> > and Postfix will drain the queue.
>
> Thanks, except that it does not send even when VPN is up. I get the same
> message and I can get it to send only when I change my relayhost back to the
> default.
For the remote relayhost trick to work,
1) the remote relayhost must not accept mail whe VPN is down.
2) the remote relayhost must only accept mail when the VPN is up.
If that is not possible, try
3) One of the "defer_transports" methods given in this thread.
4) Relaying through an SSH tunnel that listens on 127.0.0.1.
5) RFC 2549 avian carriers.
Wietse
