The upgrade to vCenter Server 6.5 affects other software components of the data center.
Upgrading vCenter Server and Related VMware Products and Components summarizes how upgrading vCenter Server can affect your data center components.
vCenter Server 6.5 can manage ESXi version 5.5 or 6.0 hosts in the same cluster with ESXi 6.5 hostsvCenter Server 6.5 cannot manage ESXi 5.1 or earlier hosts.
You cannot upgrade to vCenter Server 6.5 from vCenter Server 5.1 or earlier. You must first upgrade to vCenter Server version 5.5 or 6.0.
|Product or Component||Compatibility|
|vCenter Server||Verify support for the upgrade path from your current version of vCenter Server to your planned upgrade version. See the VMware Product Interoperability Matrix at http://www.vmware.com/resources/compatibility/sim/interop_matrix.php.|
|vCenter Server database||Verify that your database is supported for the vCenter Server version that you are upgrading to. Upgrade the database if necessary. See the VMware Product Interoperability Matrix at http://www.vmware.com/resources/compatibility/sim/interop_matrix.php.
Note: vCenter Server Appliance for vCenter Server 6.5 uses PostgreSQL for the embedded database. vCenter Server Appliance 6.5 does not support external databases.
|vSphere Web Client||Verify that your vSphere Web Client works with the vCenter Server version that you are upgrading to. For best performance and compatibility, upgrade your vSphere Web Client to the same version as your vCenter Server. See the VMware Product Interoperability Matrix at http://www.vmware.com/resources/compatibility/sim/interop_matrix.php.|
|ESX and ESXi hosts||Verify that your ESX or ESXi host works with the vCenter Server version that you are upgrading to. Upgrade if necessary. See the VMware Product Interoperability Matrix at http://www.vmware.com/resources/compatibility/sim/interop_matrix.php.|
|VMFS-3 volumes||You can continue to use existing VMFS-3 datastores, but you cannot create VMFS-3 datastores. If you have VMFS-3 datastores, upgrade them to VMFS-6.|
|Virtual machines||Upgrade options depend on your current version. See Upgrading Virtual Machines and VMware Tools.|
|VMware Tools||Upgrade options depend on your current version. See the information about upgrading VMware Tools in Upgrading Virtual Machines and VMware Tools.|
|Auto Deploy||To ensure compatibility and best performance, when you upgrade to vCenter Server 6.5, use Auto Deploy to upgrade ESXi hosts to the same version.|