Anti-affinity rule for control plane nodes

[vxav]

Is your feature request related to a problem? Please describe.

The control plane nodes should be spread on different vSphere hosts.

Describe the solution you'd like

Add an interface to the clusters with flags to:

• Create affinity rule. Or maybe it's best to create it by default and control the enabled state.
• Set to should or must (required unchecked)

The members of the anti-affinity rule should be re-evaluated when the cluster is changed (scaling, rolling...).

https://docs.vmware.com/en/VMware-Cloud-Director/10.4/VMware-Cloud-Director-Tenant-Portal-Guide/GUID-402BC249-FAD9-408D-90DA-4ADE657B608B.html

Describe alternatives you've considered

No response

Additional context

No response

[dlipovetsky]

What does this require from the VCD provider?

Does it require placement policies?

The CAPVCD types would need to add support for the "failure domain" concept from Cluster API.

[vxav]

It requires the controllers to create and maintain an anti-affinity rule with the CP nodes as members. It does not require the use of placement policies. When the maintainers get to the implementation of failure domains then they will need placement policies I believe.