Hello John, Phil,

have you managed to look at the information in the link below? I think
dm-multihost is as module.

Regards,
Remek

Here is all the information I collected: http://pastebin.com/VF4Sfrq5


Regarding the testing setup, we can safely consider whole system as a
test, we will rebuild the system once we figure final config anyway.
So we can play around with the current raid with no risk of data loss.