Merge pull request #27032 from robscott/topology-aware-hints

Adding documentation for Topology Aware Hints

content/en/docs/tasks/administer-cluster/enabling-service-topology.md

@@ -8,9 +8,12 @@ content_type: task
 ---
 
 <!-- overview -->
-This page provides an overview of enabling Service Topology in Kubernetes.
-
+{{< feature-state for_k8s_version="v1.21" state="deprecated" >}}
 
+This feature, specifically the alpha topologyKeys API, is deprecated in
+Kubernetes v1.21. [Topology Aware
+Hints](/docs/concepts/services-networking/topology-aware-hints) was introduced
+in Kubernetes v1.21 and provides similar functionality.
 
 ## {{% heading "prerequisites" %}}
 

content/en/docs/tasks/administer-cluster/enabling-topology-aware-hints.md

@@ -0,0 +1,39 @@
+---
+reviewers:
+- robscott
+title: Enabling Topology Aware Hints
+content_type: task
+min-kubernetes-server-version: 1.21
+---
+
+<!-- overview -->
+{{< feature-state for_k8s_version="v1.21" state="alpha" >}}
+
+_Topology Aware Hints_ enable topology aware routing with topology hints
+included in EndpointSlices. This approach tries to keep traffic close to where
+it originated from. This can result in decreased costs and improved performance.
+
+## {{% heading "prerequisites" %}}
+
+  {{< include "task-tutorial-prereqs.md" >}} {{< version-check >}}
+
+The following prerequisite is needed in order to enable topology aware hints:
+
+* {{< glossary_tooltip text="Kube-proxy" term_id="kube-proxy" >}} running in
+  iptables mode or IPVS mode
+* Ensure that you have not disabled EndpointSlices
+
+## Enable Topology Aware Hints
+
+To enable service topology, enable the `TopologyAwareHints` [feature
+gate](docs/reference/command-line-tools-reference/feature-gates/) for the
+kube-apiserver, kube-controller-manager, and kube-proxy:
+
+```
+--feature-gates="TopologyAwareHints=true"
+```
+
+## {{% heading "whatsnext" %}}
+
+* Read about [Topology Aware Hints](/docs/concepts/services-networking/topology-aware-hints) for Services
+* Read [Connecting Applications with Services](/docs/concepts/services-networking/connect-applications-service/)