High availability

High availability ensures that system services and data remain accessible with minimal downtime by distributing compute, control, and storage components across independent failure domains.

In the IBM Fusion HCI solution, high availability refers to deployment configurations that maintain continuous operation and data integrity even in the event of major infrastructure failures, such as the loss of a rack, availability zone, or network domain.

The architecture eliminates single points of failure by distributing control-plane nodes, storage replicas, and compute resources across discrete failure domains or availability zones.

The IBM Fusion HCI offers the following multi rack topology to support the high availability for the OpenShift® Container Platform cluster:

2AZ and arbiter node topology

A deployment configuration that spans two availability zones with an additional arbiter node located in a third zone. The arbiter node maintains cluster quorum and allows continued operation in case of a zone or rack failure. This option offers a cost-effective balance between high availability and resource utilization. For more information, see 2AZ and arbiter node configuration with Fusion Data Foundation.