Standard Configuration with Controller StorageΒΆ

StarlingX supports a small-scale deployment option using a small Ceph cluster as a back-end for Kubernetes PVCs deployed on the controller nodes instead of using dedicated storage nodes.

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See Common Components for a description of common components of this deployment configuration.

This deployment configuration consists of a two node HA controller+storage cluster managing up to 200 worker nodes. The limit on the size of the worker node pool is due to the performance and latency characteristics of the small integrated Ceph cluster on the controller+storage nodes.

This configuration optionally uses dedicated physical disks configured on each controller+storage node as Ceph OSDs. The typical solution requires one primary disk used by the platform for system purposes and subsequent disks are used for Ceph OSDs.

Optionally, instead of using an internal Ceph cluster across controllers, you can configure an external Netapp Trident storage backend.

On worker nodes, the primary disk is used for system requirements and for container local ephemeral storage.

HA controller services run across the two controller+storage nodes in either Active/Active or Active/Standby mode. The two node Ceph cluster on the controller+storage nodes provides HA storage through OSD replication between the two nodes.

In the event of an overall controller+storage node failure, all controller HA services become active on the remaining healthy controller+storage node, and the above mentioned nodal Ceph replication protects the Kubernetes PVCs.

On overall worker node failure, hosted application containers on the failed worker node are recovered on the remaining healthy worker nodes.