Configure a Pod Quota for a Namespace

This page shows how to set a quota for the total number of Pods that can run in a namespace. You specify quotas in a ResourceQuota object.

Before you begin

You need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. If you do not already have a cluster, you can create one by using minikube or you can use one of these Kubernetes playgrounds:

• Katacoda
• Play with Kubernetes

Create a namespace

Create a namespace so that the resources you create in this exercise are isolated from the rest of your cluster.

kubectl create namespace quota-pod-example

Create a ResourceQuota

Here is the configuration file for a ResourceQuota object:

admin/resource/quota-pod.yaml

apiVersion: v1
kind: ResourceQuota
metadata:
  name: pod-demo
spec:
  hard:
    pods: "2"

Create the ResourceQuota:

kubectl apply -f https://k8s.io/examples/admin/resource/quota-pod.yaml --namespace=quota-pod-example

View detailed information about the ResourceQuota:

kubectl get resourcequota pod-demo --namespace=quota-pod-example --output=yaml

The output shows that the namespace has a quota of two Pods, and that currently there are no Pods; that is, none of the quota is used.

spec:
  hard:
    pods: "2"
status:
  hard:
    pods: "2"
  used:
    pods: "0"

Here is the configuration file for a Deployment:

admin/resource/quota-pod-deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: pod-quota-demo
spec:
  selector:
    matchLabels:
      purpose: quota-demo
  replicas: 3
  template:
    metadata:
      labels:
        purpose: quota-demo
    spec:
      containers:
      - name: pod-quota-demo
        image: nginx

In the configuration file, replicas: 3 tells Kubernetes to attempt to create three Pods, all running the same application.

Create the Deployment:

kubectl apply -f https://k8s.io/examples/admin/resource/quota-pod-deployment.yaml --namespace=quota-pod-example

View detailed information about the Deployment:

kubectl get deployment pod-quota-demo --namespace=quota-pod-example --output=yaml

The output shows that even though the Deployment specifies three replicas, only two Pods were created because of the quota.

spec:
  ...
  replicas: 3
...
status:
  availableReplicas: 2
...
lastUpdateTime: 2017-07-07T20:57:05Z
    message: 'unable to create pods: pods "pod-quota-demo-1650323038-" is forbidden:
      exceeded quota: pod-demo, requested: pods=1, used: pods=2, limited: pods=2'

Clean up

Delete your namespace:

kubectl delete namespace quota-pod-example

What's next

For cluster administrators

• Configure Default Memory Requests and Limits for a Namespace

• Configure Default CPU Requests and Limits for a Namespace

• Configure Minimum and Maximum Memory Constraints for a Namespace

• Configure Minimum and Maximum CPU Constraints for a Namespace

• Configure Memory and CPU Quotas for a Namespace

• Configure Quotas for API Objects

For app developers

• Assign Memory Resources to Containers and Pods

• Assign CPU Resources to Containers and Pods

• Configure Quality of Service for Pods