[Exim] virtual users, same domain, multiple servers on intra…

I have installed exim 3.35 on 3 machines

   one.foo.bar
   two.foo.bar       - no direct connection to the Internet
   three.foo.bar     - no direct connection to the Internet

MX for foo.bar resolves to host one.foo.bar

exim @ one.foo.bar aliases *@foo.bar to
user@??? or user@??? or user@???
(works well)

I am still trying to resolve two issues

1. (two|three).foo.bar have alias lists that resolve to their respectively
hosted users, but mail sent to anything@??? i wouldlike routed to
one.foo.bar

2. (this i think i can manage by reading more) since (two|three).foo.bar
are not going to be connected to the Internet I would like all non local
mail to be routed to one.foo.bar

Currently, i'm working with alias files, but eventually I will be
integrating everything to ldap (master on one.foo.bar and replicated to
(two|three).foo.bar.

Any advice from good souls appreciated.

Brendon
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