image I got a note about SQL Server versions from our very own Mounia Rachidi over in Microsoft France and I thought it would be a good idea to mention it here since this is something that the product documentation doesn’t necessary spell out. 

Apparently Mounia was working with a customer who was using SCVMM 2007 and this customer had about 200 hosts.  What was happening was that the SQL database got full (which obviously caused problems) but it was unclear why this was happening. 

Well it turns out the reason was because we were using the Express version of SQL server and the Express version only supports a maximum database size of 4GB.  When looking at the documented requirements for SCVMM 2007 it doesn’t specify the type of the database server to use while managing a high number of servers, but the same documentation for SCVMM 2008 clearly states that you should be using the full version of SQL Server when managing a large number of hosts:

“Note: The SQL Server 2005 Express Edition SP2 database size is limited to 4 GB, and so it is recommended that you use a full version of SQL Server when the VMM server is managing more than 150 hosts.”

A quick check with the product team verified that yes, in this respect the SQL requirements are the same, so once the database was moved to a full version of SQL the problems were resolved. 

So remember, if you’re only managing a small number of hosts then the Express Edition is probably fine, but if you ever decide to expand to 150 or more hosts then moving to the full version of SQL Server should be in your plans.