Microsoft SQL Server 2012 Express Edition is included in the Veeam Backup & Replication setup, which is a convenient option; on the other hand, it has several limitations:
▪Uses 1 GB of RAM for the SQL Express Server (see https://msdn.microsoft.com/en-us/library/cc645993(v=SQL.110).aspx#CrossBoxScale).
▪SQL Express uses only the first CPU. If possible, configure 4 cores for the CPU (see https://msdn.microsoft.com/en-us/library/cc645993(v=SQL.110).aspx#CrossBoxScale).
▪Database size cannot exceed 10GB. That is enough to handle the environments with 400 – 500 VMs, as the configuration database will likely to be below 10 GB. However, if you plan to back up more VMs, it is recommended that you use Standard or Enterprise Edition of Microsoft SQL Server, otherwise, the Veeam Backup & Replication console and job processing will work slower than needed (due to memory and CPU limitations).
Another consideration relates to disaster recovery plans. By default, Veeam Explorer for Microsoft SharePoint and Veeam Explorer for Microsoft SQL will use a local SQL Server instance as a staging system for database restore (for details, see) – and SQL databases in production environment are likely to exceed 10 GB, so Express Edition will not be able to support them.
Thus, it is necessary to use Standard or Enterprise Edition if you plan to do any of the following:
▪Process more than 4000 VMs (also recommended for 400 – 4000 VMs).
▪Use Veeam Explorer for Microsoft SQL Server or Veeam Explorer for Microsoft SharePoint with databases bigger than 10 GB. If using any special features of Microsoft SQL Server or Microsoft SharePoint that are only available with Standard or Enterprise edition of SQL Server, you have to use the corresponding version with Veeam.
In other deployment cases, accepting the limitations, it is possible to use Microsoft SQL Server Express Edition.
To improve performance of Microsoft SQL Express version, it is recommended that you add multiple cores to the first CPU.