Viktor Dukhovni:
> On Thu, Jun 16, 2022 at 07:35:20PM -0400, Wietse Venema wrote:
>
> > Bob Proulx:
> > > Is there a transport mapping equivalent to match against the MX host
> > > instead of against the the recipient address? That's really what is
> > > desired here. I didn't think such a feature existed yet.
> >
> > it would require a Postfix lookup table that returns MX hosts for
> > a domain,
> >
> > pipemap:{domain-to-mx, inline:{ {.google.com = slow:} }
> >
> > plus some safeguard to avoid doing this for local deliveries.
>
> Transport resolution does remote DNS lookups will be a prohibitive
> performance bottleneck on systems delivering a steady non-trivial stream
> of mail. The queue manager is not multi-threaded, and each recipient
> domain can/will incur some delay.
We'd obviously have to make some lookups asynchronous.
But the core problem is harder: using a key-value protocol to
generate transport:nexthop from DNS lookup results.
Wietse
