If you are in NON HA mode and you lose any node your cluster will be offline.
The master holds all the customisation ( policies, alarms users access etc) so you can imagine what would happen if you lose it
the data will not have its data replicated to the other nodes so if you lose it the database will be inconsistent and be offline.
Either way it does not matter what was collecting data it wont fail over to the other due to the cluster being offline.
I am basing this on 6.1 but think it still holds true in 6.7