Two-Node with Arbiter

A Two-Node OpenShift with Arbiter (TNA) cluster is a compact, cost-effective OKD topology. The topology consists of two control plane nodes and a lightweight arbiter node. The arbiter node stores the full etcd data, maintaining an etcd quorum and preventing split brain. The arbiter node does not run the additional control plane components kube-apiserver and kube-controller-manager, nor does it run workloads.

To install a Two-Node OpenShift with Arbiter cluster, assign an arbiter role to at least one of the nodes and set the control plane node count for the cluster to 2. Although OKD does not currently impose a limit on the number of arbiter nodes, the typical deployment includes only one to minimize the use of hardware resources.

After installation, you can add additional arbiter nodes to a Two-Node OpenShift with Arbiter cluster but not to a standard multi-node cluster. It is also not possible to convert between a Two-Node OpenShift with Arbiter and standard topology.

You can install a Two-Node Arbiter cluster by using one of the following methods: