restructuring autoscaling in eck

Author: charlotte-hoblik

deploy-manage/autoscaling.md

@@ -33,6 +33,6 @@ Autoscaling is not supported on Debian 8.
 Find instructions on setting up and managing autoscaling, including supported environments, configuration options, and examples:
 
 * [Autoscaling in {{ece}} and {{ech}}](/deploy-manage/autoscaling/autoscaling-in-ece-and-ech.md)
-* [Autoscaling in {{eck}}](TODO)
+* [Autoscaling in {{eck}}](/deploy-manage/autoscaling/autoscaling-in-eck.md)
 * [Autoscaling deciders](/deploy-manage/autoscaling/autoscaling-deciders.md)
 * [Trained model autoscaling](/deploy-manage/autoscaling/trained-model-autoscaling.md)

deploy-manage/autoscaling/deployments-autoscaling-on-eck.md renamed to deploy-manage/autoscaling/autoscaling-in-eck.md

@@ -1,12 +1,16 @@
 ---
 mapped_pages:
   - https://www.elastic.co/guide/en/cloud-on-k8s/current/k8s-autoscaling.html
+  - https://www.elastic.co/guide/en/cloud-on-k8s/current/k8s-stateless-autoscaling.html
 applies_to:
   deployment:
     eck: ga
 ---
+# Autoscaling in {{eck}}
 
-# Deployments autoscaling on ECK [k8s-autoscaling]
+Configure autoscaling for Elasticsearch deployments in {{eck}}. Learn how to enable autoscaling, define policies, manage resource limits, and monitor scaling. Includes details on autoscaling stateless applications like Kibana, APM Server, and Elastic Maps Server.
+
+## Deployments autoscaling on ECK [k8s-autoscaling]
 
 ::::{note}
 Elasticsearch autoscaling requires a valid Enterprise license or Enterprise trial license. Check [the license documentation](../license/manage-your-license-in-eck.md) for more details about managing licenses.
@@ -16,12 +20,12 @@ Elasticsearch autoscaling requires a valid Enterprise license or Enterprise tria
 ECK can leverage the [autoscaling API](https://www.elastic.co/docs/api/doc/elasticsearch/group/endpoint-autoscaling) introduced in Elasticsearch 7.11 to adjust automatically the number of Pods and the allocated resources in a tier. Currently, autoscaling is supported for Elasticsearch [data tiers](/manage-data/lifecycle/data-tiers.md) and machine learning nodes.
 
 
-## Enable autoscaling [k8s-enable]
+### Enable autoscaling [k8s-enable]
 
 To enable autoscaling on an Elasticsearch cluster, you need to define one or more autoscaling policies. Each autoscaling policy applies to one or more NodeSets which share the same set of roles specified in the `node.roles` setting in the Elasticsearch configuration.
 
 
-### Define autoscaling policies [k8s-autoscaling-policies]
+#### Define autoscaling policies [k8s-autoscaling-policies]
 
 Autoscaling policies can be defined in an `ElasticsearchAutoscaler` resource. Each autoscaling policy must have the following fields:
 
@@ -93,7 +97,7 @@ In the case of storage the following restrictions apply:
 * Scaling up (vertically) is only supported if the available capacity in a PersistentVolume matches the capacity claimed in the PersistentVolumeClaim. Refer to the next section for more information.
 
 
-### Scale Up and Scale Out [k8s-autoscaling-algorithm]
+#### Scale Up and Scale Out [k8s-autoscaling-algorithm]
 
 In order to adapt the resources to the workload, the operator first attempts to scale up the resources (cpu, memory, and storage) allocated to each node in the NodeSets. The operator always ensures that the requested resources are within the limits specified in the autoscaling policy. If each individual node has reached the limits specified in the autoscaling policy, but more resources are required to handle the load, then the operator adds some nodes to the NodeSets. Nodes are added up to the `max` value specified in the `nodeCount` of the policy.
 
@@ -129,7 +133,7 @@ spec:
 ```
 
 
-### Set the limits [k8s-autoscaling-resources]
+#### Set the limits [k8s-autoscaling-resources]
 
 The value set for memory and CPU limits are computed by applying a ratio to the calculated resource request. The default ratio between the request and the limit for both CPU and memory is 1. This means that request and limit have the same value. You can change the default ratio between the request and the limit for both the CPU and memory ranges by using the `requestsToLimitsRatio` field.
 
@@ -165,7 +169,7 @@ spec:
 You can find [a complete example in the ECK GitHub repository](https://github.com/elastic/cloud-on-k8s/blob/2.16/config/recipes/autoscaling/elasticsearch.yaml) which will also show you how to fine-tune the [autoscaling deciders](/deploy-manage/autoscaling/autoscaling-deciders.md).
 
 
-### Change the polling interval [k8s-autoscaling-polling-interval]
+#### Change the polling interval [k8s-autoscaling-polling-interval]
 
 The Elasticsearch autoscaling capacity endpoint is polled every minute by the operator. This interval duration can be controlled using the `pollingPeriod` field in the autoscaling specification:
 
@@ -197,10 +201,10 @@ spec:
 ```
 
 
-## Monitoring [k8s-monitoring]
+### Monitoring [k8s-monitoring]
 
 
-### Autoscaling status [k8s-autoscaling-status]
+#### Autoscaling status [k8s-autoscaling-status]
 
 In addition to the logs generated by the operator, an autoscaling status is maintained in the `ElasticsearchAutoscaler` resource. This status holds several `Conditions` to summarize the health and the status of the autoscaling mechanism. For example, dedicated `Conditions` may report if the controller cannot connect to the Elasticsearch cluster, or if a resource limit has been reached:
 
@@ -237,7 +241,7 @@ kubectl get elasticsearchautoscaler autoscaling-sample \
 ```
 
 
-### Expected resources [k8s-autoscaling-expected-resources]
+#### Expected resources [k8s-autoscaling-expected-resources]
 
 The autoscaler status also contains a `policies` section which describes the expected resources for each NodeSet managed by an autoscaling policy.
 
@@ -273,7 +277,7 @@ kubectl get elasticsearchautoscaler.autoscaling.k8s.elastic.co/autoscaling-sampl
 ```
 
 
-### Events [k8s-events]
+#### Events [k8s-events]
 
 Important events are also reported through Kubernetes events, for example when the maximum autoscaling size limit is reached:
 
@@ -284,7 +288,7 @@ Important events are also reported through Kubernetes events, for example when t
 ```
 
 
-## Disable autoscaling [k8s-disable]
+### Disable autoscaling [k8s-disable]
 
 You can disable autoscaling at any time by deleting the `ElasticsearchAutoscaler` resource. For machine learning the following settings are not automatically reset:
 
@@ -294,3 +298,50 @@ You can disable autoscaling at any time by deleting the `ElasticsearchAutoscaler
 
 You should adjust those settings manually to match the size of your deployment when you disable autoscaling.
 
+## Autoscaling stateless applications on ECK [k8s-stateless-autoscaling]
+
+::::{note} 
+This section only applies to stateless applications. Check [Elasticsearch autoscaling](#k8s-autoscaling) for more details about scaling automatically Elasticsearch.
+::::
+
+
+The [Horizontal Pod Autoscaler](https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale) can be used to automatically scale the deployments of the following resources:
+
+* Kibana
+* APM Server
+* Elastic Maps Server
+
+These resources expose the `scale` subresource which can be used by the Horizontal Pod Autoscaler controller to automatically adjust the number of replicas according to the CPU load or any other custom or external metric. This example shows how to create an `HorizontalPodAutoscaler` resource to adjust the replicas of a Kibana deployment according to the CPU load:
+
+```yaml
+apiVersion: elasticsearch.k8s.elastic.co/v1
+kind: Elasticsearch
+metadata:
+  name: elasticsearch-sample
+spec:
+  version: 8.16.1
+  nodeSets:
+    - name: default
+      count: 1
+      config:
+        node.store.allow_mmap: false
+
+apiVersion: autoscaling/v2beta2
+kind: HorizontalPodAutoscaler
+metadata:
+  name: kb
+spec:
+  scaleTargetRef:
+    apiVersion: kibana.k8s.elastic.co/v1
+    kind: Kibana
+    name: kibana-sample
+  minReplicas: 1
+  maxReplicas: 4
+  metrics:
+    - type: Resource
+      resource:
+        name: cpu
+        target:
+          type: Utilization
+          averageUtilization: 50
+```

deploy-manage/autoscaling/autoscaling-stateless-applications-on-eck.md

@@ -56,7 +56,7 @@ Other sections of the documentation also include relevant configuration options
 
 * [Remote clusters](/deploy-manage/remote-clusters/eck-remote-clusters.md)
 
-* [Autoscaling](../../autoscaling/deployments-autoscaling-on-eck.md)
+* [Autoscaling](../../autoscaling/autoscaling-in-eck.md#k8s-autoscaling.md)
 
 * [Stack monitoring](/deploy-manage/monitor/stack-monitoring/eck-stack-monitoring.md): Monitor your {{es}} cluster smoothly with the help of ECK.
 

deploy-manage/deploy/cloud-on-k8s/elasticsearch-configuration.md

@@ -29,6 +29,6 @@ The following sections describe how to customize a {{kib}} deployment to suit yo
     * [Disable TLS](k8s-kibana-http-configuration.md#k8s-kibana-http-disable-tls)
     * [Install {{kib}} plugins](k8s-kibana-plugins.md)
 
-* [Autoscaling stateless applications](../../autoscaling/autoscaling-stateless-applications-on-eck.md): Use [Horizontal Pod Autoscaler](https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale/) for {{kib}} or other stateless applications.
+* [Autoscaling stateless applications](../../autoscaling/autoscaling-in-eck.md#k8s-stateless-autoscaling): Use [Horizontal Pod Autoscaler](https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale/) for {{kib}} or other stateless applications.
 
 

deploy-manage/deploy/cloud-on-k8s/kibana-configuration.md

@@ -22,7 +22,7 @@ When orchestrating any of these applications, also consider the following topics
 * [Access Elastic Stack services](accessing-services.md)
 * [Customize Pods](customize-pods.md)
 * [Manage compute resources](manage-compute-resources.md)
-* [Autoscaling stateless applications](../../autoscaling/autoscaling-stateless-applications-on-eck.md)
+* [Autoscaling stateless applications](../../autoscaling/autoscaling-in-eck.md#k8s-stateless-autoscaling)
 * [Elastic Stack configuration policies](elastic-stack-configuration-policies.md)
 * [Upgrade the Elastic Stack version](../../upgrade/deployment-or-cluster.md)
 * [Connect to external Elastic resources](connect-to-external-elastic-resources.md)

deploy-manage/deploy/cloud-on-k8s/orchestrate-other-elastic-applications.md

@@ -485,8 +485,7 @@ toc:
   - file: autoscaling.md
     children:
       - file: autoscaling/autoscaling-in-ece-and-ech.md
-      - file: autoscaling/autoscaling-stateless-applications-on-eck.md
-      - file: autoscaling/deployments-autoscaling-on-eck.md
+      - file: autoscaling/autoscaling-in-eck.md
       - file: autoscaling/autoscaling-deciders.md
       - file: autoscaling/trained-model-autoscaling.md
   - file: remote-clusters.md