Enable XFS Quota on LocalPV Hostpath

This document provides the necessary steps to enable and configure XFS Quota on OpenEBS LocalPV HostPath. By following these instructions, you will install the OpenEBS LocalPV provisioner, create a StorageClass with XFS Quota support, and set up a PersistentVolumeClaim (PVC) to apply project quotas on the local volumes. It also includes the process for mounting the volume to an application pod and verifying that the quota is successfully applied.

Install the OpenEBS Dynamic LocalPV Provisioner#

Refer to the OpenEBS Installation documentation to install the OpenEBS LocalPV Hostpath Provisioner.

Create StorageClass#

To create a hostpath StorageClass with the XFSQuota configuration option, use the following YAML definition. This configuration will enable the XFSQuota for the specified path and storage type.

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: openebs-hostpath-xfs
  annotations:
    openebs.io/cas-type: local
    cas.openebs.io/config: |
      - name: StorageType
        value: "hostpath"
      - name: BasePath
        value: "/var/openebs/local/"
      - name: XFSQuota
        enabled: "true"
provisioner: openebs.io/local
volumeBindingMode: WaitForFirstConsumer
reclaimPolicy: Delete

For advanced configuration of XFSQuota, you may also set the softLimitGrace and hardLimitGrace parameters, which define the storage capacity limits beyond the Persistent Volume (PV) storage request. The updated YAML definition is as follows:

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: openebs-hostpath-xfs
  annotations:
    openebs.io/cas-type: local
    cas.openebs.io/config: |
      - name: StorageType
        value: "hostpath"
      - name: BasePath
        value: "/var/openebs/local/"
      - name: XFSQuota
        enabled: "true"
        data:
          softLimitGrace: "0%"
          hardLimitGrace: "0%"
provisioner: openebs.io/local
volumeBindingMode: WaitForFirstConsumer
reclaimPolicy: Delete

note

softLimitGrace and hardLimitGrace are used in conjunction with the PV storage request to determine the soft and hard limits of the quota.
The size of these limits is calculated as "Size of PV storage request * (1 + LimitGrace%)"
If no values are specified, the default is softLimitGrace: "0%" / hardLimitGrace: "0%", meaning the storage capacity is limited to the PV storage request value.
For example, with a PV of 100Gi capacity and values softLimitGrace: "90%" / hardLimitGrace: "100%", the soft limit will be set to 190Gi, and the hard limit will be set to 200Gi. You can select to use either softLimitGrace or hardLimitGrace independently based on your requirements.
Refer to the relevant xfs_quota documentation for more detailed instructions regarding the configuration of soft and hard limits.

Create a PVC#

To create a PVC using the StorageClass's name, use the following definition:

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: local-hostpath-xfs
spec:
  storageClassName: openebs-hostpath-xfs
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 5Gi

At this stage, the PVC will remain in the 'Pending' state until the volume is successfully mounted.

Verify the PVC status.

$ kubectl get pvc

Example Output

NAME                  STATUS    VOLUME   CAPACITY   ACCESS MODES   STORAGECLASS           AGE
local-hostpath-xfs    Pending                                      openebs-hostpath-xfs   21s

Mount the Volume#

Mount the volume to the application pod container. A sample BusyBox Pod template is as follows:

apiVersion: v1
kind: Pod
metadata:
  name: busybox
spec:
  volumes:
  - name: local-storage
    persistentVolumeClaim:
      claimName: local-hostpath-xfs
  containers:
  - name: busybox
    image: busybox
    command:
       - sh
       - -c
       - 'while true; do echo "`date` [`hostname`] Hello from OpenEBS Local PV." >> /mnt/store/greet.txt; sleep $(($RANDOM % 5 + 300)); done'
    volumeMounts:
    - mountPath: /mnt/store
      name: local-storage

The PVC status will change to 'Bound' once the volume is successfully mounted and the quota will be applied.

Verify that the XFS project quota is applied.

$ sudo xfs_quota -x -c 'report -h' /var/openebs/local/

Example Output

Project quota on /var/openebs/local (/dev/loop16)
                        Blocks
Project ID   Used   Soft   Hard Warn/Grace
---------- ---------------------------------
#0              0      0      0  00 [------]
#1              0   5.7G   6.7G  00 [------]

Limitation#

Resizing of quota is not supported.