# Limit Storage Consumption

LLMS index: [llms.txt](/llms.txt)

---

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This example demonstrates how to limit the amount of storage consumed in a namespace.

The following resources are used in the demonstration: [ResourceQuota](/docs/concepts/policy/resource-quotas/),
[LimitRange](/docs/tasks/administer-cluster/manage-resources/memory-default-namespace/),
and [PersistentVolumeClaim](/docs/concepts/storage/persistent-volumes/).


## Before you begin


* <p>You need to have a Kubernetes cluster, and the kubectl command-line tool must
be configured to communicate with your cluster. It is recommended to run this tutorial on a cluster with at least two nodes that are not acting as control plane hosts. If you do not already have a
cluster, you can create one by using
<a href="https://minikube.sigs.k8s.io/docs/tutorials/multi_node/">minikube</a>
or you can use one of these Kubernetes playgrounds:</p>
<ul>
<li><a href="https://labs.iximiuz.com/playgrounds?category=kubernetes&filter=all">iximiuz Labs</a></li>
<li><a href="https://killercoda.com/playgrounds/scenario/kubernetes">Killercoda</a></li>
<li><a href="https://kodekloud.com/public-playgrounds">KodeKloud</a></li>
</ul>
 
  <p>To check the version, enter  <code>kubectl version</code>.</p>




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## Scenario: Limiting Storage Consumption

The cluster-admin is operating a cluster on behalf of a user population and the admin wants to control
how much storage a single namespace can consume in order to control cost.

The admin would like to limit:

1. The number of persistent volume claims in a namespace
2. The amount of storage each claim can request
3. The amount of cumulative storage the namespace can have


## LimitRange to limit requests for storage

Adding a `LimitRange` to a namespace enforces storage request sizes to a minimum and maximum. Storage is requested
via `PersistentVolumeClaim`. The admission controller that enforces limit ranges will reject any PVC that is above or below
the values set by the admin.

In this example, a PVC requesting 10Gi of storage would be rejected because it exceeds the 2Gi max.

```yaml
apiVersion: v1
kind: LimitRange
metadata:
  name: storagelimits
spec:
  limits:
  - type: PersistentVolumeClaim
    max:
      storage: 2Gi
    min:
      storage: 1Gi
```

Minimum storage requests are used when the underlying storage provider requires certain minimums. For example,
AWS EBS volumes have a 1Gi minimum requirement.

## ResourceQuota to limit PVC count and cumulative storage capacity

Admins can limit the number of PVCs in a namespace as well as the cumulative capacity of those PVCs. New PVCs that exceed
either maximum value will be rejected.

In this example, a 6th PVC in the namespace would be rejected because it exceeds the maximum count of 5. Alternatively,
a 5Gi maximum quota when combined with the 2Gi max limit above, cannot have 3 PVCs where each has 2Gi. That would be 6Gi requested
 for a namespace capped at 5Gi.

```yaml
apiVersion: v1
kind: ResourceQuota
metadata:
  name: storagequota
spec:
  hard:
    persistentvolumeclaims: "5"
    requests.storage: "5Gi"
```

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## Summary

A limit range can put a ceiling on how much storage is requested while a resource quota can effectively cap the storage
consumed by a namespace through claim counts and cumulative storage capacity. The allows a cluster-admin to plan their
cluster's storage budget without risk of any one project going over their allotment.