Situation as follows: mixed cluster with 3.5 and 3.6 nodes. Now in the process of reinstalling the 3.5 nodes with 3.6 on CentOS 7.2. I can't live migrate VM's while they're running on different versions. That's odd, but not the weirdest issue.

The most interesting part is happening when I power down a VM, and then run it on a 3.6 node. Only on CentOS 7 VM's, I'm getting a "no bootable device" error. I have a mixed setup of ubuntu, CentOS 6 and CentOS 7. Ubuntu & CentOS 6 are fine. 

Tried shooting grub in MBR again, to no effect. I start the VM then on a 3.5 node and all is fine.
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