Is it possible to update the Cluster (Pod) CIDR or Service CIDR for an RKE CLI or Rancher launched cluster post-provisioning?

Question

The Cluster (Pod) CIDR (default 10.42.0.0/16) and Service CIDR (default 10.43.0.0/16) ranges for a cluster can be specified in the cluster configuration YAML when launching a Kubernetes cluster via both the RKE CLI and Rancher v2.x. Is it possible to change these values after the cluster has been provisioned?

Pre-requisites

• A Kubernetes cluster launched by the RKE CLI, or Rancher v2.x

Answer

Updating either the Cluster (Pod) CIDR or Service CIDR after the cluster has been provisioned is not supported and you should be careful to set these as required when first configuring the cluster.