Hi everyone

I had a discussion a few days ago in the #openstack-nova about the possibility of introducing the concept of different failure domains, which would be a component inside of an availability zone.   The concept is similar to Azure’s availability set feature:

https://learn.microsoft.com/en-us/azure/virtual-machines/availability-set-overview

I’ve built a very similar nova scheduler filter which leverages server groups + another scheduler hint called `different_failure_domain` then it will actually build them inside different failure domains.  The failure domains are built similar to AZs in terms of being modeled are using aggregates, so it would use a `failure_domain` aggregate metadata.

I’ve managed to build and validate this functionality with my team here:

https://github.com/vexxhost/nova-scheduler-filters

Now, based on that, I’m wondering if:

1. Is this the best approach to take based on this?
2. Is this something we can upstream into Nova easily as an extra filter?  I think this is helpful for a lot of the “VMware” world people. 😊

Thanks,

Mohammed