[EXIM] routing and rewriting

Top Page
Delete this message
Reply to this message
Author: Philip Hazel
Date:  
To: Leonardo Boselli
CC: exim-users
Subject: [EXIM] routing and rewriting
On Mon, 1 Feb 1999, Leonardo Boselli wrote:

> > However, rewriting is not usually the best way to do routing.
> Why ?


I suppose this is a philosophical point really. There are people who
don't like rewriting at all, because it hides things. Personally, I'm
quite happy with using it for hiding login names, setting up corporate
domains in outgoing mail etc. I'm less comfortable with the idea of
using it as a routing tool. I prefer to see routing done by routers.

If you route the address a@??? to the host x.y.z using rewriting, then
the envelope that arrives at x.y.z is "a@???", which is not the
envelope that the message started out with, though of course in the body
of the message you may well still have

To: a@???

depending on whether you rewrote that or not. I suppose there are cases
where you want this to happen, but my view is that if the problem you
are trying to solve is purely one of routing a message to a particular
host, then you should do just that, and leave the envelope alone.


-- 
Philip Hazel            University of Cambridge Computing Service,
ph10@???      Cambridge, England. Phone: +44 1223 334714.



--
*** Exim information can be found at http://www.exim.org/ ***