Comment 7 for bug 1686514

Stephen,
I believe the linked branch has a suitable fix for this issue now.

In response to my comment #6, I've realized that the 'replace_fs' in fs_setup configuration was always ignored, because if a partition is provided (in the "dotted" format there), then replace_fs is not used.

I've tested the general path on azure by re-formatting/partitioning the disk into something that looks like a newly partitioned disk and then rebooting.