Use case Overview:
As a CNS 3.9 user, I want to ensure my data is stored on an arbiter volume that is converted from a two-way replicated volume.
refer to https://bugzilla.redhat.com/show_bug.cgi?id=1591624#c4 for details on how to create block hosting volume as arbiter volume.
I am not sure if Chapter 5 is the right place to add this info.
It belongs to heketi configuration.