replicas

Change the number of replicas for a resource.

Given this kubernetes Deployment fragment:

kind: Deployment
metadata:
  name: deployment-name
spec:
  replicas: 3

one can change the number of replicas to 5 by adding the following to your kustomization:

apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization

replicas:
- name: deployment-name
  count: 5

This field accepts a list, so many resources can be modified at the same time.

As this declaration does not take in a kind: nor a group: it will match any group and kind that has a matching name and that is one of:

  • Deployment
  • ReplicationController
  • ReplicaSet
  • StatefulSet

For more complex use cases, revert to using a patch.

Example

Input File

# deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: the-deployment
spec:
  replicas: 5
  template:
    containers:
      - name: the-container
        image: registry/container:latest
# kustomization.yaml
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization

replicas:
- name: the-deployment
  count: 10

resources:
- deployment.yaml

Output

# deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: the-deployment
spec:
  replicas: 10
  template:
    containers:
      - name: the-container
        image: registry/container:latest