I currently manage an Exchange 2003 server with about 135 mailboxes. Out of those 135, 45 are active users and the rest are service accounts and mailboxes used with our document imaging system. The size of the DB is about 275GB.
I have a 3 host vSphere 5.1 cluster and I'm starting to virtualize all my servers (about 16 production servers).
For storage I have a fibre EMC VNX5300 SAN and for backup software I have Veeam Backup and CA Arcserve R16 for my physical servers.
I'm looking for recommendations on virtualizing Exchange 2007. I can’t go with Exch 2010 or 2013 because some bad purchasing decisions were made before I started with the company and we did not purchase Exchange with software assurance so as long as it is supported I am planning to run 2007. I have vSphere Essentials Plus so no DRS or SDRS.
-Is my environment small enough that I will be able to run multiple roles on the same server or is splitting the roles recommended? If so, how many servers?
-I am not planning to use CCR or at least not for now. Can I use vSphere HA?
-Should I worry about VMFS vs RDM for the storage type?
-Besides the obvious of separating OS, DB and logs, is there other must do best practices you can recommend?
-Is it okay to put OS files on a RAID 5 LUN and DB and logs on a RAID 10?
Any advice and recommendation are always welcome.