You can upgrade to Cloud Foundation 2.1.2 only if you are at Cloud Foundation 2.1.1. If your environment includes a Cloud Foundation version prior to 2.1.1, you must first upgrade to 2.1.1 and then upgrade to 2.1.1.
About this task
Upgrading Cloud Foundation is a multi step process. You must follow each step in the order in which it is documented.
Complete the Prerequisites for Upgrading VMware Software