rancher-sandbox / cluster-api-addon-provider-fleet

Cluster API Add-on Provider for Fleet will auto register child clusters with fleet.
Apache License 2.0
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Explore cluster move and pivot procedure using Fleet #35

Open Danil-Grigorev opened 2 months ago

Danil-Grigorev commented 2 months ago

We need to explore the possibility of moving the cluster and cluster API operator definitions from the management cluster to the child cluster, using the provisioned fleet installation by the cluster API Adon Provider Fleet.

This would involve storing the definitions of the cluster API operator from the management cluster in a set of bundle resources and targeting the child cluster to provision those and collecting all the cluster and related cluster resources from the management cluster and moving them across to the child cluster.

Thanks to alternative communication pattern, this is possible with fleet's ability to connect from the child cluster back to the management cluster, and therefore there's no need for Cluster API kubeconfig management->child connection to execute those operations. Whole process can be fully automated.

For the pivot procedure, which originally involves creating a temporary bootstrap cluster to provision target management cluster and then executing move procedure from the original management cluster to the target management cluster, we can explore possibility of using in place upgrades to treat the temporary bootstrap cluster as the target management cluster first and therefore there is no need to deploy a temporary cluster and destroy it afterwards.