Register service.alpha.kubernetes.io/tolerate-unready-endpoints Ann… (#39122)

* Registered service.alpha.kubernetes.io/tolerate-unready-endpoints Annotation

* Update content/en/docs/reference/labels-annotations-taints/_index.md

Co-authored-by: Qiming Teng <[email protected]>

* Update content/en/docs/reference/labels-annotations-taints/_index.md

Co-authored-by: Tim Bannister <[email protected]>

---------

Co-authored-by: Qiming Teng <[email protected]>
Co-authored-by: Tim Bannister <[email protected]>

Author: 3 people

content/en/docs/reference/labels-annotations-taints/_index.md

@@ -171,6 +171,16 @@ There are two possible values:
 - `onstart`: The APIService should be reconciled when an API server starts up, but not otherwise.
 - `true`: The API server should reconcile this APIService continuously.
 
+### service.alpha.kubernetes.io/tolerate-unready-endpoints (deprecated)
+
+Used on: StatefulSet
+
+This annotation on a Service denotes if the Endpoints controller should go ahead and create Endpoints for unready Pods.
+Endpoints of these Services retain their DNS records and continue receiving
+traffic for the Service from the moment the kubelet starts all containers in the pod
+and marks it _Running_, til the kubelet stops all containers and deletes the pod from
+the API server.
+
 ### kubernetes.io/hostname {#kubernetesiohostname}
 
 Example: `kubernetes.io/hostname: "ip-172-20-114-199.ec2.internal"`