I am supporting a small company, 10 users, which is upgrading from Win 2000 Server and Exchange Server 2000 to 2003. The upgrade will include a new computer. The vendor sales person is urging us to go with two servers, one for the Active Driectory and one for Exchange Server. The present computer is a P III 733 MHz with a RAID 5, 54 GB pack. There was no performance or storage issues with this computer. The reason we are upgrading is the computer's mother board is causing some problems and we were condering upgrading anyway. Most of the company's business and storage is handeled with propriarity sofware on a UNIX server which is running just fine.
My question is: Is there a compelling reason to go with two, rather than one server? I have no problem with going with a XEON processor and much larger drives, but considering the relative smallness and low server usage of the company, is a two server system warrented? I have heard the arguments for - from the vendor - but is there a COMPELLING reason for two servers?