Best Practice: Location for Backup Exec Database (BEDB).
By default, Backup Exec (BE) will install a SQL Express Instance named (BKUPEXEC) as the home for the BE database named (BEDB). This is the recommenced instance and best practice for where the BE database should be mounted.
SQL Express is a smaller free version of SQL. SQL Express can be installed on a server that is also running other SQL Express Instances or Full versions of SQL. A server can have up to 16 instances of SQL Express on it.
The BE Database can be mounted in a Full version of SQL. Please note that when BE applies updates it will stop the instance. Thus any other databases in the same instance will lose connectivity during this action. This is why it is recommended to have the BE Database in an instance by itself. If a remote SQL instance is used, BE must have good network connectivity to the instance or errors will occur in BE. This why the default local SQL Express instance is recommended.
SQL Express 2005 has a size limit of 4GB, and SQL Express 2008 is 10GB. Only very large deployments of BE, normally using the Central Admin Option, have a database grow to the point that exceeds this 4GB limit.