High availability

This page describes your high availability (HA) options in GKE On-Prem.

HA for user clusters

Beta

This product or feature is subject to the "Pre-GA Offerings Terms" in the General Service Terms section of the Service Specific Terms. Pre-GA products and features are available "as is" and might have limited support. For more information, see the launch stage descriptions.

GKE On-Prem architecture with highly-available user clusters (Click to enlarge)

GKE On-Prem supports HA user control planes. During cluster creation, you can choose to create three user control planes. To do so, specify usercluster.masternode.replicas: 3 in the GKE On-Prem configuration file you're using to create the user cluster.

To create a HA user cluster, GKE On-Prem creates three user control plane VMs (or master nodes) within the admin cluster. Each control plane VM runs the same Kubernetes control plane components. GKE On-Prem uses leader election to

Note: During this feature's beta phase, DRS anti-affinity rules are not created for user cluster control plane VMs. You can expect this feature in a future release. Until that time, you should enable vSphere High Availability.

Caveats

Currently, you cannot resume cluster creation for a HA user cluster.

HA for admin clusters

GKE On-Prem does not currently support HA admin control planes. You can prevent a single point of failure in the admin cluster by enabling vSphere High Availability for your vSphere cluster.

vSphere High Availability protects GKE On-Prem admin clusters from going down in the event of an underlying host failure.

To learn more, see Create a vSphere HA Cluster.