On 9 Oct 2001, Paul Crowley wrote:
> I've often wished Exim supported the creation of arbitrary "chains" of
> routers, the way the "ipchains" Linux firewalls of the 2.2 era allows
> chains of firewall rules. You could add a special router that
> directed a message to a router chain. Then you could have a single
> rule at the start of your "entry chain" which checked the domain of a
> message against local_domains, and sent it off to an appropriate chain
> if so.
Exim 4 doesn't have local_domains, but I take it you mean "some list of
local domains". But what you have suggested just reimplements the
initial global/local split which I'm getting away from.
> This makes it very straightforward to replicate the behaviour
> of Exim 3 in a flexible way that adds a great deal of power to message
> handling.
It isn't hard to replicate the default configuration behaviour of Exim
3. The first router checks for local domains, and if not, does a DNS
lookup and fails if it finds nothing. The remaining routers behave like
Exim 3 directors.
> Am I making any sense? Is it too late to propose a change of this
> magnitude?
Yes. Yes.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
