Sorry - forgot to reply to the list!
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What we are now trying to do is have exim recognize several final destinations.
Question 1: If we list several mail servers in the route list will exim try each one if delivery fails on another one?
Question 2: Can a router be built to do what I asked in question 1?
Alternative: If we set up a private record in each person's DNS, say a text record, with a code name indicating the mail server they reside on, is there any logic we can build into the router to pick up record from the DNS, match it against a file that translates the code name to a server host name, then have that automatically inserted into the router's route list?
GA
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Hi, the "route_list" and "route_data" options support a semi-colon seperated list of hosts or ip addresses, see the links below:
http://www.exim.org/exim-html-4.62/doc/html/spec_html/ch20.html#id2614498
http://www.exim-new-users.co.uk/index.php?searchword=route_list&option=com_search&Itemid=
You can also find a paper to explain this in more detail here (see page 34 for manualroute to multiple targets):
http://www.exim-new-users.co.uk/Integrating_Exim_with_Exchange_Tutorial_v.1.1.pdf
You might want to consider a "redirect" router that exaimnes the "local_part" to decide whichn destination server to send the message to instead of creating new records in dns (start with a simple text file first, then use a fast simple db like "cdb" once you have it working).
You might also want to consider the hosts_randomize option:
http://www.exim-new-users.co.uk/index.php?searchword=hosts_randomize&option=com_search&Itemid=
Thanks
Jason_Meers