How to Determine the Rancher Leader, in Rancher v2.x

Task

During troubleshooting it may be useful to know which of the Rancher server pods, running as part of the rancher Deployment in the cattle-system namespace, is the current leader, and this article details the steps to determine this.

Pre-requisites

• Rancher v2.x installed in a Kubernetes cluster

Steps

Via the Rancher UI

1. Navigate to the local cluster in which Rancher is installed.

2. Click the Projects/Namespaces tab, and select the System project.

3. Under the Resources tab, select Config.

4. Locate the cattle-controllers ConfigMap, under the kube-system namespace.

5. Expand the Labels & Annotations section and note the current leader pod name in the holderIdentity field.

Via kubectl with a script

With the kubeconfig for the Rancher server cluster sourced, the leader can be determined using the following script:

curl https://raw.githubusercontent.com/rancherlabs/support-tools/master/troubleshooting-scripts/determine-leader/rancher2_determine_leader.sh | sh

Further reading

• Rancher Documentation on Troubleshooting the Rancher Server Kubernetes Cluster