What is the difference in cluster methods from kubernetes docs site?

snorkelbuckle

Slightly confused here while reviewing kubernetes docs, the section "Bootstrapping clusters with kubeadm". What is the difference between this:

• Set up a High Availability etcd cluster with kubeadm

and this:

• Creating Highly Available clusters with kubeadm

Are these mutually exclusive? If not what would be the reasons to use one or the other or both? Is a load balancer used with the second method?

Thanks.

chrispokorni

Hi @snorkelbuckle,

Based on etcd's capabilities, there are two types of HA Kubernetes cluster topologies - see the two diagrams for stacked and external etcd.

Creating HA clusters with kubeadm includes steps specific for each of the two HA topologies, while the HA etcd cluster is only part of one of the two topologies (with external etcd).

A load balancer/proxy is required by both HA Kubernetes cluster topologies.

Regards,
-Chris

snorkelbuckle

Thank you Chris, that helps.

Does this mean based on what I see in the topology diagrams, that etcd is not running on the control plane nodes if using with external etcd?

chrispokorni

Yes, based on the description of the external etcd topology, each etcd instance runs on its own dedicated host.

Regards,
-Chris