On Wed, 22 Jun 2005 17:23:22 BST, Tony Finch said:
You need a table of name -> location mappings which each mail server can use to route email. You could distribute the table using whatever technology you like, e.g. LDAP. Google for Schlumberger Exim LDAP for a complicated example, though it can be done much more simply.
That's all fine and good once the mail gets into his e-mail infrastructure. The problem he's going to hit is that he wants *my* mail server to send mail to 'fred@example.com' to get routed to the MX in San Fran where Fred is, and *my* mail server to send mail 'johann@example.com' to get routed to the MX in Geneva where Johann is, and avoid having a central MX that then does routing. And basically, he's screwed, because the MX lookup is only based on the RHS of the target address. AT *best* he can deploy a @NN.example.com and have different MX entries for US.example.com and FR.example.com and so on (but he already said that's a suboptimal).