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Smart hosts

Question about smart host and forward all mails with unresolved resicpients to host

Our exchange servers are configured to route mails to unix host for external recipients
in Default SMTP Virtual Server properties, in Message tab, we can forward to a host
Can we forward to multiple hosts using the following:
in Delivery Tab, Advanced, Smart Host: can we do the same?

in Routing groups, Connectors
can ve set the same in SMTP Connector: Forward all mails through... using the same list of IP addresses.

Mails are externally routed to unix boxes located in various countries and this would help us to balance the load and or be sure that a stopped mailer will not interrupt the mail flow.


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1 Solution
For something this advanced I would think about a load balancer and simply using one VIP or a Virtual IP that would round robin or load balance between other IP's to more traffice too.
just a though.


If you have multiple Exchange servers, I would setup SMTP connectors with the same cost and configure them as SMART HOSTS to the Unix boxes.

You can then setup your unix boxes to forward email back to Exchange - Setup Round Robin DNS externally.
stefriAuthor Commented:
Thanks for input but using RoundRobin DNS is out of scope

What I am aiming is just to forward mails to external mailers (costs are not involved).
We have 4 external MX mailers. Those 4 receive from Internet and we want to forward external mails to any one of those mailers

I am a little confused with the documentation which mentions hostS and the gui which says host (no plural S).
What can I trust: doc or gui?
They are production servers and I cant play with configuration...users would be quite disappointed if everything stops.

ANother thing to do is have 2 gateway smarthosts ready. Create an SMTP connector (like mentioned before) with the same costs and add all the servers you want used for this purpose. Then have the connector point to one of the 2 relays. When something goes wrong with one relay, implement the second one. Here is why I say this. We have an SMTP relay in San Fran and one in New York. We have 2 Internal Exchange servers acting as gateways with an SMTP connector using only those 2 to point to San Fran Relay. When something goes wrong we simply repoint the SMTP smart host to new york. Now all email gets routed that way.

HOpe I didn't confuse you.


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