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content/en/docs/concepts/extend-kubernetes/api-extension/apiserver-aggregation.md

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 The aggregation layer allows Kubernetes to be extended with additional APIs, beyond what is offered by the core Kubernetes APIs.
 The additional APIs can either be ready-made solutions such as [service-catalog](/docs/concepts/extend-kubernetes/service-catalog/), or APIs that you develop yourself.
 
 The aggregation layer is different from [Custom Resources](/docs/concepts/extend-kubernetes/api-extension/custom-resources/), which are a way to make the {{< glossary_tooltip term_id="kube-apiserver" text="kube-apiserver" >}} recognise new kinds of object.
 
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 ## Aggregation layer
 
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 `EnableAggregatedDiscoveryTimeout=false` [feature gate](/docs/reference/command-line-tools-reference/feature-gates/) on the kube-apiserver
 to disable the timeout restriction. This deprecated feature gate will be removed in a future release.
 
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 * To get the aggregator working in your environment, [configure the aggregation layer](/docs/tasks/access-kubernetes-api/configure-aggregation-layer/).
 * Then, [setup an extension api-server](/docs/tasks/access-kubernetes-api/setup-extension-api-server/) to work with the aggregation layer.
 * Also, learn how to [extend the Kubernetes API using Custom Resource Definitions](/docs/tasks/access-kubernetes-api/extend-api-custom-resource-definitions/).
 * Read the specification for [APIService](/docs/reference/generated/kubernetes-api/{{< param "version" >}}/#apiservice-v1-apiregistration-k8s-io)
 
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