Our existing Exchange 2003 STD installation runs on one server that host all exchange functions including OWA. We have around 150 mail boxes and our private store is close to the 75GB ceiling. We are planning to move up to Exchange 2010 on a virtual server. Can we duplicate our current setup and run all exchange rolls on a single server our do we need to use two servers and split out the Exchange rolls.

You can install all roles on a single server (excluding the Edge role which is optional).Tim Harrington | MVP: Exchange | MCITP: EMA 2007/2010, MCITP: Lync 2010, MCITP: Server 2008, MCTS: OCS | Blog: http://HowDoUC.blogspot.com | Twitter: @twharrington

You can do a single server deployment, but for that many users I would not recomend it. I would suggest you initially deploy 2 servers, one for the mailbox, and a second for the hub transport and CAS roles. This gives you the ability to easily add a 2nd mailbox server for database redundancy either immeaditly, or later on. Also review the following document for memory sizing on the mailbox server http://technet.microsoft.com/en-us/library/ee832793.aspx

Hi, 8 GB of RAM is the minimum supported. More information: http://technet.microsoft.com/en-us/library/dd346700.aspx Hope it helps. Rowen TechNet Community Support

Thanks everyone for the feedback.