Do We Need To Use Identical CPUs to Configure OpenStack For the First Time?

Question

In terms of CPUs and OpenStack configuration does all the following solutions hold?

1. All CPUs need to be identical (e.g., XEON E5).

2. CPUs can be from the same vendor and family; but with different versions (e.g., XEON E5 and XEON E3).

3. CPUs can be from different vendors (e.g., Intel and AMD).