In vCenter Server 5.x the embedded SQL Express database supports a maximum of 5 hosts and 50 Virtual Machines. With vCenter Server 6 the embedded database is changes from SQL Express to a vPostgress database. The vPostgres database supports a maximum of 20 hosts and 200 VMs. In comparison the vPostgres database on the vCenter Server Appliance (VCSA) 6 supports 1000 hosts and 10000. When upgrading or fresh installing vCenter Server 6 make sure to note the following items:
- When upgrading to vCenter Server 6.0, the Microsoft SQL Express database is migrated to a vPostgres database.
- Oracle, SQL Standard and Enterprise database editions will not be migrated to vPostgres.
- It is possible to upgrade without migrating the SQL database to vPostgres. Make sure you have a supported SQL database before upgrading. More information can be found here, link.
- When uninstalling vCenter Server 6 the embedded VMware vPostgres database will be removed with all the data! More information can be found here, link.
- How to backup and restore the vPostgres database there is a Python script available. This script can be found here, link.
- VMware vSphere Update Manager can’t use the embedded vPostgres database! For VMware vSphere Update Manager you need a Microsoft SQL (Express) database. When combining the vCenter Server, PSC and VUM on one server, two different databases engines are used. This looks like this: