Kubernetes Pod Warning: 1 node(s) had volume node affinity conflict

Question

I try to set up Kubernetes cluster. I have Persistent Volume, Persistent Volume Claim and Storage class all set-up and running but when I wan to create pod from deployment,

Answer 1

The error "volume node affinity conflict" happens when the persistent volume claims that the pod is using are scheduled on different zones, rather than on one zone, and so the actual pod was not able to be scheduled because it cannot connect to the volume from another zone. To check this, you can see the details of all the Persistent Volumes. To check that, first get your PVCs:

$ kubectl get pvc -n <namespace>

Then get the details of the Persistent Volumes (not Volume claims)

$  kubectl get pv

Find the PVs, that correspond to your PVCs and describe them

$  kubectl describe pv <pv1> <pv2>

You can check the Source.VolumeID for each of the PV, most likely they will be different availability zone, and so your pod gives the affinity error. To fix this, create a storageclass for a single zone and use that storageclass in your PVC.

kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
  name: region1storageclass
provisioner: kubernetes.io/aws-ebs
parameters:
  type: gp2
  encrypted: "true" # if encryption required
volumeBindingMode: WaitForFirstConsumer
allowedTopologies:
- matchLabelExpressions:
  - key: failure-domain.beta.kubernetes.io/zone
    values:
    - eu-west-2b # this is the availability zone, will depend on your cloud provider
    # multi-az can be added, but that defeats the purpose in our scenario