A couple of questions Do people set the -isexcludedfromprovisioning flag so new mailboxes dont get auto created on the specific archive database Other than using the set-mailbox command to specify the archive mailbox database, is there a way to set this at a "server level" so every new mailbox that is created on the server via the automatic load balancer, gets assigned to a specfic archive database

The best practice is to NOT have a dedicated archive database. I suppose your approach would be possible, but see here for why you shouldn't do this: http://blogs.technet.com/b/perryclarke/archive/2010/08/13/archiving-questions-do-tiered-storage-and-stubbing-make-sense.aspx The feature you describe would be like an mailbox template, which Exchange does not use. you could easily write a powershell file to create mailboxes in this way. Mike Crowley | MVP My Blog -- Planet Technologies

So i guess why did MS then add this feature in SP1? The aim would be to have pst files go directly into the online archive database and thus reduce the amount data in the primary database. This also tends to reduce the amount of replicated storage consumed as with a DAG for very high redundancy they recommend 3 copies when using a jbod disk layout. The other aim is reducing backups and recovery times. Exchange 2010 can already exist on very cheap disk, so the traditional archiving reasons i guess a not really valid.

The feature was added because many customers asked for it. Mike Crowley | MVP My Blog -- Planet Technologies

Ok so is it better to put everthing in the primary store? My fear is in our world we will have several databases 1tb in size within 18mths, so would have to then employ a retention policy to move them to an archive store anyways

I’m not sure what you mean “primary store”. I am not saying you shouldn’t use the online archive. I am just saying Microsoft recommends a good blend of IO loads across all databases. If your databases are too large or over IO capacity that’s a problem; but not related to archives necessarily. Check out the Exchange Storage calculator to help you plan your environment: http://blogs.technet.com/b/exchange/archive/2011/05/18/the-mailbox-server-role-requirements-calculator-now-with-database-copy-distribution.aspx Mike Crowley | MVP My Blog -- Planet Technologies