Starting with vSphere 6.7, VMware announced a simplified vCenter Single Sign-On domain architecture by enabling vCenter Enhanced Linked Mode support for vCenter Server Appliance installations with an embedded Platform Services Controller. You can use the vCenter Server converge utility to change the deployment topology from an external Platform Services Controller to an embedded Platform Services Controller with support for vCenter Enhanced Linked Mode. As of this release, the external Platform Services Controller architecture is deprecated and will not be available in future releases.
Workaround:
To work around this issue, converge the external Platform Services Controller on vCenter Server 6.5.x/6.7.x with vCenter Server.
For more information, see Changing external Platform Services Controller deployment to embedded during process of migration or upgrade
For vCenter Server 6.5, Converge needs to be performed using Converge Tool, Refer to Understanding the vCenter Server Converge Tool for more information about the Tool.
Note: If you have an external Platform Services Controller for vCenter Server 6.0, then first upgrade to vCenter Server 6.5 or 6.7 then use the converge utility convert the external Platform Services Controller node to an embedded Platform Services Controller node. For more information, see:
Best practices for upgrading to vCenter Server 6.5
Best practices for upgrading to vCenter Server 6.7