CloudNativePG operator should be installed in namespace "{{ .Release.Namespace }}". You can now create a PostgreSQL cluster with 3 nodes in the current namespace as follows: cat <<EOF | kubectl apply -f - # Example of PostgreSQL cluster apiVersion: postgresql.cnpg.io/v1 kind: Cluster metadata: name: cluster-example spec: instances: 3 storage: size: 1Gi EOF kubectl get cluster