We now have the time to shuffle things around and possibly look at upgrading to Exchange 2010. But for now need to make our Exchange 2007 environment secure. Here is the scenario. We have 1 Mail Box server and 1 CAS server. The MB server is within out network on a vlan used for servers, the CAS server is in our DMZ along with our webserver and a couple other servers. with a whole whack load of ports opened up for it to talk through. Not ideal. We deploy to Blackberry devices, iPhones and iPad's so both BES and ActiveSync are used. What would be the best pratice (layout) for an Exchange 2007 server to be able to deliver content through ActiveSync, internally, and through OWA for external access? Would we be able to remove the CAS serve from the equation, or should we keep it in case we add another MB server for fault tolerance? Ideally I would like to have 2 MB servers for fault tolerance and load balancing in the near future. Knowing what I would need for servers and roles would be beneficial now so I can make changes or be ready if an upgrade to 2010 is required. Thanks for any advice guys and gals!

Hi First.. CAS should NOT be put on DMZ, it should be located on the internal LAN like your other server. The only exchange server role that should be put in DMZ is Edge server. Best practice for publishing ActiveSync is to use ISA Server/TMG and publish the needed services. ISA/TMG can handle OWA,EAS,OA In your case I would plan for a upgrade, so make a proper design on Exchange 2010, ex.. 3 servers with MBX,CAS,HUB and put them into a DAG, then use a HWLB for load balancing the traffic. The third MBX(DAG) server can be put in lagged mode up to 14 days so you avoid corrupted databases. More about the licensing: http://www.microsoft.com/exchange/2010/en/us/licensing.aspx Jonas Andersson MCTS: Microsoft Exchange Server 2007/2010 | MCITP: EMA 2007/2010 | MCSE/MCSA Blog: http://www.testlabs.se/blog

Thank you Jonas. This is exactly what I was looking for.

You're welcome! :)Jonas Andersson MCTS: Microsoft Exchange Server 2007/2010 | MCITP: EMA 2007/2010 | MCSE/MCSA Blog: http://www.testlabs.se/blog