You can change the Kubernetes Classless Inter-domain Routing (CIDR) subnet masks after deployment.

The vRealize Orchestrator Appliance configures and runs a Kubernetes cluster. The pods and services in this cluster are deployed in separate IPv4 subnets, represented by the internal cluster CIDR and internal service CIDR, respectively. The default values of the subnet masks set during OVF deployment are the following:

Kubernetes network property Default value Property description
cluster-cidr 10.244.0.0/22 The CIDR used for pods running inside the Kubernetes cluster.
service-cidr 10.244.4.0/22 The CIDR used for Kubernetes services inside the Kubernetes cluster.

The default CIDR network addresses can create a conflict with outside private networks that you might be using. In such scenarios, you can change the configuration of these CIDR values either during or after deploying your vRealize Orchestrator Appliance.

Note: For information on changing the CIDR configuration during appliance deployment, see Download and Deploy the vRealize Orchestrator Appliance.

Prerequisites

  • Verify that the CIDR address values support at least 1024 hosts.
  • The internal cluster CIDR and internal service CIDR must not share the same subnet value.
  • The CIDR value for one of the subnets cannot include the value you want to add to the other subnet.
    Note: For example, the cluster-cidr value cannot be 10.244.4.0/22 10.244.4.0/24, because this would also include the subnet value for the service-cidr property. Each subnet value must be added separately.

Procedure

  1. Log in to the vRealize Orchestrator Appliance as root.
  2. Run the vracli upgrade exec -y --prepare --profile k8s-subnets command.
  3. Back up your vRealize Orchestrator deployment by taking a virtual machine (VM) snapshot. See Take a Snapshot of a Virtual Machine.
    Caution: vRealize Orchestrator 8.x does not currently support memory snapshots. Before taking the snapshot of your vRealize Orchestrator deployment, verify that the Snapshot the virtual machine’s memory option is deactivated.
  4. Change the values of the cluster CIDR and service CIDR subnets by running the vracli network k8s-subnets command. 
    vracli network k8s-subnets --cluster-cidr <CIDR_value> --service-cidr <CIDR_value>
  5. To finish the CIDR configuration process, run the vracli upgrade exec command.