Hands-On Microservices with Kubernetes

Updating the link-manager service to match blue pods only

The service, as you may recall, matches any pods with the svc: link and app: manager labels:

$ kubectl get svc link-manager -o custom-columns=SELECTOR:.spec.selectorSELECTOR map[app:manager svc:link]

By adding the deployment: blue label, we didn't interfere with the matching. However, in preparation for our green deployment, we should make sure that the service only matches the pods of the current blue deployment. Let's add the deployment: blue label to the service's selector:

selector: app: manager svc: link deployment: blue

We can verify that it worked by using the following command:

$ kubectl get svc link-manager -o custom-columns=SELECTOR:.spec.selector SELECTOR map[app:manager ...