docs(kapsule): add etcd clean-up tutorial

pages/kubernetes/how-to/recover-space-etcd.mdx

@@ -0,0 +1,54 @@
+---
+meta:
+title: Recovering ETCD database space for a Kapsule/Kosmos cluster
+description: Learn how to reclaim database space for your Kubernetes Kapsule and Kosmos clusters to stay below your quota.
+content:
+h1: Recovering ETCD database space for a Kapsule/Kosmos cluster
+paragraph: Learn how to reclaim database space for your Kubernetes Kapsule and Kosmos clusters to stay below your quota.
+tags: kubernetes kapsule kosmos etcd
+dates:
+validation: 2025-04-01
+posted: 2025-04-01
+categories:
+  - containers
+---
+
+Kubernetes Kapsule clusters have quotas on the space they can occupy on an etcd database. See Kapsule [cluster-types](https://api.scaleway.com/k8s/v1/regions/fr-par/cluster-types) for details on each offer.
+You can see your current cluster space consumption at any time in your cluster grafana dashboard (`Etcd disk usage` panel).
+This guide helps you to free up space on your database to avoid reaching this limit.
+
+<Macro id="requirements" />
+
+- [Created](/kubernetes/how-to/create-cluster/) a Kubernetes Kapsule cluster
+- [Downloaded](/kubernetes/how-to/connect-cluster-kubectl/) the Kubeconfig
+
+* Looking for unused resources is a good approach, delete any Secrets, large ConfigMaps that are not used anymore in your cluster.
+
+  ```sh
+  > kubectl -n $namespace delete $ConfigMapName
+  ```
+
+* keep an eye on Helm Charts that are deploying a lot of custom resources (CRDs), they tend to fill up etcd space. You can find them by showing resource kinds
+
+  ```sh
+  > kubectl api-resources
+  NAME                                SHORTNAMES                          APIVERSION                           NAMESPACED   KIND
+  configmaps                          cm                                  v1                                   true         ConfigMap
+  endpoints                           ep                                  v1                                   true         Endpoints
+  events                              ev                                  v1                                   true         Event
+  cronjobs                            cj                                  batch/v1                             true         CronJob
+  jobs                                                                    batch/v1                             true         Job
+  [...]
+  ```
+Look for resources with an external apiversion (not _v1_, _apps/v1_, _storage.k8s.io/v1_ or _batch/v1_ for example).
+
+<Message type="note">
+    It is known that cluster with many nodes and with at least one GPU node may have a lot of _nodefeatures_ objects polluting their etcd space. We are working on a long-term fix but for now manually deleting these objects and downsizing the cluster (or upgrading to a dedicated offer with a bigger etcd quota) is the best solution.
+</Message>
+
+* If you have a doubt on space taken by a resource, you can dump it to get its size
+
+  ```sh
+  > kubectl get nodefeature -n kube-system   $node-feature-name -o yaml | wc -c
+    305545 // ~300KiB, big object
+  ```