[SOLVED] How to enable ReadWriteMany access mode using an io2 EBS Volume

How to enable ReadWriteMany access mode using an io2 EBS Volume

I want to enable ReadWriteMany access mode in EKS Persistent Volume. Came accross io2 volumetype by EBS AWS. SO using io2 type volume

storage_class.yaml

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: io2
provisioner: ebs.csi.aws.com
volumeBindingMode: WaitForFirstConsumer
parameters:
  type: io2
  iopsPerGB: "200"

persistent_volume.yaml

apiVersion: v1
kind: PersistentVolume
metadata:
  name: pv
spec:
  accessModes:
  - ReadWriteMany
  awsElasticBlockStore:
    fsType: ext4
    volumeID: <IO2 type volume ID>
  capacity:
    storage: 50Gi
  storageClassName: io2
  volumeMode: Filesystem

pv_claim.yaml

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pvc
spec:
  accessModes:
  - ReadWriteMany
  resources:
    requests:
      storage: 50Gi
  volumeMode: Filesystem
  volumeName: pv
  storageClassName: io2

When 3 replicas of pods are deployed across 2 nodes in same AZ, 2 replicas (on one node) successfully mounts to the io2 volume and starts running but third replica on another node does not mount to volume.

Error -> Unable to attach or mount volumes: unmounted volumes['']

Also, I want to understand if io2 type volumes are meant to be mount to multiple nodes(EC2 instances in same AZ as volume) in EKS with ReadWriteMany access mode.

Solution

I looks like there is open feature request on kubernetes-sigs/aws-ebs-csi-driver repo but no progress on this. So I guess that it is not supported at the moment but you can monitor the issue for updates.