Cloning Clusters
If you have a cluster in Rancher that you want to use as a template for creating similar clusters, you can use Rancher CLI to clone the cluster's configuration, edit it, and then use it to quickly launch the cloned cluster.
Duplication of imported clusters is not supported.
Cluster Type | Cloneable? |
---|---|
Nodes Hosted by Infrastructure Provider | ✓ |
Hosted Kubernetes Providers | ✓ |
Custom Cluster | ✓ |
Imported Cluster |
Warning: During the process of duplicating a cluster, you will edit a config file full of cluster settings. However, we recommend editing only values explicitly listed in this document, as cluster duplication is designed for simple cluster copying, not wide scale configuration changes. Editing other values may invalidate the config file, which will lead to cluster deployment failure.
Prerequisites
Download and install Rancher CLI. Remember to create an API bearer token if necessary.
1. Export Cluster Config
Begin by using Rancher CLI to export the configuration for the cluster that you want to clone.
Open Terminal and change your directory to the location of the Rancher CLI binary,
rancher
.Enter the following command to list the clusters managed by Rancher.
./rancher cluster ls
Find the cluster that you want to clone, and copy either its resource
ID
orNAME
to your clipboard. From this point on, we'll refer to the resourceID
orNAME
as<RESOURCE_ID>
, which is used as a placeholder in the next step.Enter the following command to export the configuration for your cluster.
./rancher clusters export <RESOURCE_ID>
**Step Result:** The YAML for a cloned cluster prints to Terminal.
- Copy the YAML to your clipboard and paste it in a new file. Save the file as
cluster-template.yml
(or any other name, as long as it has a.yml
extension).
2. Modify Cluster Config
Use your favorite text editor to modify the cluster configuration in cluster-template.yml
for your cloned cluster.
Note: As of Rancher v2.3.0, cluster configuration directives must be nested under the
rancher_kubernetes_engine_config
directive incluster.yml
. For more information, refer to the section on the config file structure in Rancher v2.3.0+.
Open
cluster-template.yml
(or whatever you named your config) in your favorite text editor.Warning: Only edit the cluster config values explicitly called out below. Many of the values listed in this file are used to provision your cloned cluster, and editing their values may break the provisioning process.
As depicted in the example below, at the
<CLUSTER_NAME>
placeholder, replace your original cluster's name with a unique name (<CLUSTER_NAME>
). If your cloned cluster has a duplicate name, the cluster will not provision successfully.Version: v3
clusters:
<CLUSTER_NAME>: # ENTER UNIQUE NAME
dockerRootDir: /var/lib/docker
enableNetworkPolicy: false
rancherKubernetesEngineConfig:
addonJobTimeout: 30
authentication:
strategy: x509
authorization: {}
bastionHost: {}
cloudProvider: {}
ignoreDockerVersion: trueFor each
nodePools
section, replace the original nodepool name with a unique name at the<NODEPOOL_NAME>
placeholder. If your cloned cluster has a duplicate nodepool name, the cluster will not provision successfully.nodePools:
<NODEPOOL_NAME>:
clusterId: do
controlPlane: true
etcd: true
hostnamePrefix: mark-do
nodeTemplateId: do
quantity: 1
worker: trueWhen you're done, save and close the configuration.
3. Launch Cloned Cluster
Move cluster-template.yml
into the same directory as the Rancher CLI binary. Then run this command:
./rancher up --file cluster-template.yml
Result: Your cloned cluster begins provisioning. Enter ./rancher cluster ls
to confirm. You can also log into the Rancher UI and open the Global view to watch your provisioning cluster's progress.