All Pods Share the Same app and version Labels

Updated on 2023-07-04 GMT+08:00

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Description

All pods of a Service must share the same app and version labels. app traces traffic in traffic monitoring, and version distinguishes different versions in grayscale release. If pods with different app or version labels exist, this item is abnormal.

Rectification Guide

The labels of pods are configured in spec.template.metadata.labels of the Deployment. The recommended configuration is as follows:

labels:
  app: {serviceName}
  version: v1

To modify the labels of multiple pods to the same value, perform the following steps:

View the labels configured for spec.selector.

kubectl get svc {serviceName} -o yaml

For example, the labels are app: ratings and release: istio-bookinfo.
Search for the pods of a Service by label.

kubectl get pod -n {namespace} -l app=ratings,release=istio-bookinfo

NOTE:

{namespace} is the same as the namespace of the Service.
Find the workload of a pod by the pod name.

kubectl get deployment {deploymentName} -n {namespace}
NOTE:
- Generally, the pod name is in the format of {deploymentName}-{random character string}-{random character string}.
- If no workload of a pod is found by the pod name, you need to delete residual ReplicaSets.
  To check whether there are residual ReplicaSets, perform the following steps:
  1. Query the ReplicaSets of the Deployment.
    kubectl get replicaset | grep {deploymentName}
  2. Find the ReplicaSets containing more than one pod. These ReplicaSets may be residual after label modification. You need to delete the old ReplicaSets.
    kubectl delete replicaset {replicaSetName} -n {namespace}
For details about how to modify the app and version labels of a pod, see Rectification Guide.