Hi All,

PFA the two diagrams describing placement of the VMs during normal condition and condition after two node failure in 5 node set up (Each Node can host up to 6 VMs due to memory constraints).

My question is whether this kind of VM replication as shown in the attached diagram is possible utilizing oVirt schedular.

The benefits of this kind of replication would be following :-

1. Any number of Hosts/Nodes can participate (Odd/Even) in the infrastructure.

2. We can add any number (odd/even) number of Nodes to re-balance the VM placement.

3. After node failures the Maximum number of VMs that can run on the remaining nodes can be calculated with the following formula:-

Total No. of VMs running after node failure = ((Total No. of Nodes) - (No. of failed Nodes)) * (Max. No. of VMs that can run per Node)

The attached table gives a rough calculation on maximum number VMs that can run after node failures.

Please let me know if you need any further information from my side.

Thanks

Kausik