Description of problem:

In certain circumstances, it's possible to find an introspected node doesn't has differing resources than there are matching flavors.

This leads to a fairly unhelpful error stating hosts aren't available upon deployment time.

This RFE came about after speaking with Ryan Brown; we realized it could be trapped cleanly with a clear error message helping the operator realize exactly why the host wasn't considered appropriate.

Version-Release number of selected component (if applicable):


How reproducible:

Always

Steps to Reproduce:
1. Create a flavor with a resource such as RAM that's higher than is available on the physical node in question.
2. After introspecting the overcloud nodes, run the overcloud deploy and find a 500 error.

Actual results:

500 error

Expected results:

A clear message that the node found doesn't sufficient resources to match the flavor in question.

Additional info: