How to test the raw block devices with Kubestone fio ?

[Jayjeet Chakraborty]

I have a PersistentVolumeClaim as shown below

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pvc
spec:
  accessModes:
    - ReadWriteOnce
  volumeMode: Block
  resources:
    requests:
      storage: 10Gi

This PersistentVolumeClaim allows consuming storage from the PersistentVolume given below

kind: PersistentVolume
apiVersion: v1
metadata:
  name: pv
spec:
  volumeMode: Block
  capacity:
    storage: 10Gi
  local:
    path: /dev/sdb
  nodeAffinity:
    required:
      nodeSelectorTerms:
        - matchExpressions:
            - key: kubernetes.io/hostname
              operator: In
              values:
                - node2.rook-ceph-2.schedock-pg0.clemson.cloudlab.us
  accessModes:
    - ReadWriteOnce
  persistentVolumeReclaimPolicy: Delete

As evident from the spec, it bind mounts to /dev/sdb (raw block device).

No, we consume this from a Fio job pod with specification show below.

apiVersion: perf.kubestone.xridge.io/v1alpha1
kind: Fio
metadata:
  name: fio-sample
spec:
  builtinJobFiles:
  - /jobs/rand-read.fio
  - /jobs/rand-write.fio
  image:
    name: xridge/fio:3.13
  volume:
    volumeSource:
        persistentVolumeClaim:
          claimName: pvc

But we get this error on running this POD

lly assigned kubestone/fio-sample-22z77 to node2.rook-ceph-2.schedock-pg0.clemson.cloudlab.us
  Warning  FailedMount  7s (x4 over 45s)  kubelet, node2.rook-ceph-2.schedock-pg0.clemson.cloudlab.us  Unable to attach or mount volumes: unmounted volumes=[data], unattached volumes=[data default-token-c7pqq]: volume data has volumeMode Block, but is specified in volumeMount

I am new to kubernetes and kubestone and am not sure of what is the right way to test a block device through Fio benchmark of kubestone. Any help will be highly appreciated. Thanks a lot

[Jayjeet Chakraborty]

It will be also very helpful if someone can please explain briefly how to actually test raw block devices using Kubestone Fio benchmarks. Thanks again