website/docs/tasks/administer-cluster/limit-storage-consumption.md

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---
title: Limit Storage Consumption
---
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{% capture overview %}
This example demonstrates an easy way 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/configure-pod-container/limit-range/),
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and [PersistentVolumeClaim](/docs/concepts/storage/persistent-volumes/).
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{% capture prerequisites %}
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* {% include task-tutorial-prereqs.md %}
{% endcapture %}
{% capture steps %}
## 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.
```
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.
## StorageQuota 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.
```
apiVersion: v1
kind: ResourceQuota
metadata:
name: storagequota
spec:
hard:
persistentvolumeclaims: "5"
requests.storage: "5Gi"
```
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{% endcapture %}
{% capture discussion %}
## 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.
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{% endcapture %}
{% include templates/task.md %}