---

Create your VolumePlacementStrategy along with your other storage resources:

Prerequisites

• Portworx version: 2.1.2 and above

Construct a VolumePlacementStrategy spec

1. Create a YAML file containing the following common fields. All VolumePlacementStrategy CRDs use these fields:

   • apiVersion as portworx.io/v1beta2
   • kind as VolumePlacementStrategy
   • metadata.name with the name of your strategy

   Add any of the following affinity or antiaffinity sections to the spec:

   • replicaAffinity
   • replicaAntiAffinity
   • volumeAffinity
   • volumeAntiAffinity

   This example adds a volumeAffinity rule to colocate Postgres volumes for performance:

     apiVersion: portworx.io/v1beta2
     kind: VolumePlacementStrategy
     metadata:
       name: postgres-volume-affinity
     spec:
       volumeAffinity:
         - matchExpressions:
           - key: app
             operator: In
             values:
               - postgres

2. Save and apply your spec with the kubectl apply command:

     kubectl apply -f yourVolumePlacementStrategy.yaml

Create other storage specs

Use a StorageClass

You can associate your VolumePlacementStrategy with a StorageClass and then reference that StorageClass in your PVC.

1. Create a StorageClass that references the VolumePlacementStrategy you created in the Construct a VolumePlacementStrategy spec steps above by specifying the placement_strategy parameter with the name of your VolumePlacementStrategy:

     apiVersion: storage.k8s.io/v1
     kind: StorageClass
     metadata:
       name: postgres-storage-class
     provisioner: kubernetes.io/portworx-volume
     parameters:
       placement_strategy: "postgres-volume-affinity"

2. Save and apply your StorageClass with the kubectl apply command:

     kubectl apply -f yourVolumePlacementStrategy.yaml

3. Create a PVC which references the StorageClass you created above, specifying the storageClass

     kind: PersistentVolumeClaim
     apiVersion: v1
     metadata:
        name: postgres-pvc
     spec:
        storageClassName: postgres-storage-class
        accessModes:
          - ReadWriteOnce
        resources:
          requests:
            storage: 2Gi

4. Save and apply your PVC with the kubectl apply command:

     kubectl apply -f yourPVC.yaml

Reference a VolumePlacementStrategy directly in a PVC

You can reference your VolumePlacementStrategy directly in your PVC using an annotation.

1. Create a PVC which references the VolumePlacementStrategy you created in the Construct a VolumePlacementStrategy spec steps above by specifying placement_strategy as an annotation with the name of your VolumePlacementStrategy:

     kind: PersistentVolumeClaim
       apiVersion: v1
       metadata:
         annotations: 
           placement_strategy: "postgres-volume-affinity"
         name: postgres-pvc
       spec:
         storageClassName: postgres-storage-class
         accessModes:
           - ReadWriteOnce
         resources:
           requests:
             storage: 2Gi

2. Save and apply your PVC with the kubectl apply command:

     kubectl apply -f yourPVC.yaml

Once you’ve applied your volumePlacementStrategy, StorageClass, and PVC, Portworx deploys volumes according to the rules you defined. Portworx also follows VolumePlacementStrategies when it restores volumes.

---