Merging companies......need help

[Len Conrad]

>How do I get DNS to advertise that mailboxes for companya can be found
>on companya's mail server and mailboxes for companyb can be found on
>companyb's mail server using an MX record for companyacompanyb?

you can´t

>That is, if we put aliases on all our existing mailboxes on both
>servers as user at companyacompanyb.com, how do I add an MX record that
>encourages outside mail servers to check BOTH mail servers for the
>valid recipient?

You don´t, have both mailservers accept all mail and use tables to guide 
forwarding to the other mailserver.

ie, don´t/can´t  solve with DNS protocol, but with SMTP routing

>Or am I out to lunch?????

aperitifs, at least :)))

The pb of course is maintaining these split and duplicated databases in sync.

Another solution is to have all mail MX'ed to only one mail server, which 
does the routing. Only one database to maintain. Totally transparent to 
Internet and the users.

Len

Len


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