<div>
For best fault tolerance, you need below three things<br />
Server, Disk and site Resilency<br />
<br />
With Exchange 2007, you can implement CCR.<br />
With Exchange 2010, you can implement DAG.<br />
<br />
Best practice again depends on budget. But as far I can recommend<br />
<br />
1) Mailbox and Unified roles, keep them on Physical server<br />
2) Hub/CAS can be on VM<br />
3) For HUB fault tolerance, you need to implement Hub server in each site<br />
4) For CAS, you can use NLB or Hardware load balancer like F5, Big IP or Barracuda. Hardware will be better.<br />
5) You can also use CAS array, but again it is not 100% fault tolerant, in case of any failure you just need to repoint the DNS to second CAS server.<br />
<br />
Hope this helps<br />
<br />
<br />

</div>


For best fault tolerance, you need below three things
Server, Disk and site Resilency

With Exchange 2007, you can implement CCR.
With Exchange 2010, you can implement DAG.

Best practice again depends on budget. But as far I can recommend

1) Mailbox and Unified roles, keep them on Physical server
2) Hub/CAS can be on VM
3) For HUB fault tolerance, you need to implement Hub server in each site
4) For CAS, you can use NLB or Hardware load balancer like F5, Big IP or Barracuda. Hardware will be better.
5) You can also use CAS array, but again it is not 100% fault tolerant, in case of any failure you just need to repoint the DNS to second CAS server.

Hope this helps




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I am looking at implementing exchange server and migrating all the mailboxes from the cloud to the in house environment. I would like to implement fault tolerance. I will be installing Fault tolerance HDD PSUs. I am looking at a failover such as a clustered hyper-v box , or just 2 exchange environments. I would appreciate your thoughts/experience on this, is there a best practice guide?<br />
Thanks &nbsp; &nbsp; &nbsp;<br />

</div>
</div>


I am looking at implementing exchange server and migrating all the mailboxes from the cloud to the in house environment. I would like to implement fault tolerance. I will be installing Fault tolerance HDD PSUs. I am looking at a failover such as a clustered hyper-v box , or just 2 exchange environments. I would appreciate your thoughts/experience on this, is there a best practice guide?
Thanks      


New Exchange Server Installation

Exchange is the server side of a collaborative application product that is part of the Microsoft Server infrastructure. Exchange's major features include email, calendaring, contacts and tasks, support for mobile and web-based access to information, and support for data storage.