redhat_best_placement_with_scope: the vm is being pinned to the selected host

[sigbjornaib]

In the / RedHat / Infrastructure / VM / Provisioning / Placement / redhat_best_placement_with_scope code a spesific RHV Host is selected.

This ends up with this RHV Host being added to the provisioning request, which in turns results in a VM being pinned to a single Host in RHV (Edit VM -> Host -> Start running on: Spesific Host).

This becomes a major headache when attempting to set the RHV Host to maintenance mode to perform RHV Host upgrades or other RHV Host maintenance tasks.

A RHV Cluster should be chosen for the VM, however the RHV Host selection should be avoided to allow for the VM being configured to "Start running on: Any Host in Cluster".

[itewk]

@sigbjornaib /ManageIQ/Infrastructure/VM/Provisioning/Placement/redhat_best_fit_cluster ships in the ManageIQ domain and does not select a host. In theory you could override the /Infrastructure/VM/Provisioning/Placement/default instance in your business logic domain and change the value of the redhat method to be redhat_best_fit_cluster rather then redhat_best_placement_with_scope.

I would say this should be closed as "works as designed" as I don't see anything to change here seeing as you can switch the placement method being used.

[sigbjornaib]

How can pinning of a vm to a spesific host on a rhv provider be "works as designed", when this pinning prevents the customer of performing maintenance on the rhv hypervisors?

[itewk]

@sigbjornaib i'm not saying its a good design, but in terms of this repo, its the design inherited from the upstream manageiq domain, it was a deisng decision made here, it was one made there, and the only reason we override here is to add the additional filtering capabilities.

but as i said in #141 (comment) there is a method that does what you want, its called redhat_best_fit_cluster.

maybe we should update the defaults of this repo to use that?