Adding labels
- Docker & Kubernetes course
- Intermediate
- Lesson 62/82
- 4 min
Learn to define labels in YAML.
Adding labels
Labels can be written in the YAML or added to and removed from running objects with kubectl label. Changing an existing key requires --overwrite; putting - at the end of the key removes the label:
kubectl label pod web takim=odeme
kubectl label pod web ortam=test --overwrite
kubectl label pod web takim- # remove
kubectl label pods -l app=web surum=v2 # add in bulkAdding annotations
kubectl annotate adds annotations with the same syntax as labels. Tools keep their settings in annotations (e.g. Ingress controllers, Prometheus):
kubectl annotate deploy web aciklama="ana sayfa servisi"
kubectl annotate svc web prometheus.io/scrape="true"
kubectl get deploy web -o jsonpath='{.metadata.annotations.aciklama}'Annotation values can contain spaces and long text; labels can't.
Practice Manage labels
Write three commands: add the label takim=odeme to the web pod; overwrite the ortam label with test; remove the katman label.
Starter code
# buraya yazSample solution
kubectl label pod web takim=odeme
kubectl label pod web ortam=test --overwrite
kubectl label pod web katman-Expected output
pod/web labeled pod/web labeled pod/web unlabeled
Questions and answers
Review the lesson questions together with their answers. To test yourself, solve the lesson interactively.
1 What does kubectl label pod web takim- do?
- It removes the takim label Correct answer
- It adds the takim label with an empty value
- It errors
- It deletes the pod
Explanation: The trailing hyphen means removal.
2 Remove the label.
kubectl label pod web ____kubectl label pod web takim-Explanation: A hyphen is appended to the key name.
3 Match.
| Term | Meaning |
|---|---|
label key=value |
Add a label |
--overwrite |
Change |
key- |
Remove |
annotate |
Add an annotation |