XFS Quota

Explore this Page

• Overview
• Requirements
• Enabling XFS Quota
• Managing and Modifying XFS Quota
• Modifying the XFS Quota Limits
• Limitations

Overview

To enforce storage limits, it is essential to enable and properly configure XFS project quotas. This document outlines the necessary prerequisites, installation procedures, filesystem configurations, and StorageClass setup required to enable XFS quotas.

Additionally, it describes how to create Persistent Volume Claims (PVCs), verify quota enforcement, and adjust quota limits when necessary.

By following the steps in this document, you will be able to successfully enable, configure, and manage XFS Quotas for deployments across various Linux distributions, including Ubuntu, Debian, RHEL, CentOS, and Fedora.

Requirements

To use XFS Quotas with Local PV Hostpath, ensure the following requirements are fulfilled:

• Install the xfsprogs package.
• Confirm that the filesystem type is XFS.
• Configure the filesystem to use the pquota or prjquota mount option.

Installing the xfsprogs Package

For Ubuntu/Debian Systems

sudo apt-get update
sudo apt-get install -y xfsprogs

For RHEL/CentOS Systems

sudo yum install -y xfsprogs

For Fedora Systems

sudo dnf install -y xfsprogs

Mounting the Filesystem with pquota Option

Verifying Filesystem Type

Check if the hostPath directory (/var/openebs/local by default) is using the XFS filesystem:

df -Th /var/openebs/local

Filesystem     Type  Size  Used Avail Use% Mounted on
/dev/nvme0n1p1 xfs   8.0G  959M  7.1G  12% /

If the directory does not exist yet, use the following script to determine the base directory and filesystem:

BASEPATH="/var/openebs/local"
until OUTPUT=$(df -Th $BASEPATH 2> /dev/null)
do
  BASEPATH=$(echo "$BASEPATH" | sed 's|\(.*\)/.*|\1|')
done
echo "PATH=${BASEPATH}"
echo "$OUTPUT"

Checking Existing Mount Options

Verify whether the mount options for the device include pquota or prjquota:

sudo mount | grep "^/dev/nvme0n1p1"

/dev/nvme0n1p1 on / type xfs (rw,relatime,seclabel,attr2,inode64,noquota)

If the mount options already include pquota or prjquota, you can proceed to the next section. If not, continue with Mounting the Device with pquota.

Mounting the Device with pquota

Root Filesystem

If the filesystem is mounted as the root (/), follow these steps:

1. Edit the GRUB configuration.

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   Open /etc/default/grub

   sudo vi /etc/default/grub

2. Locate the GRUB_CMDLINE_LINUX entry and append rootflags=pquota.

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   Locate GRUB_CMDLINE_LINUX Entry

   GRUB_CMDLINE_LINUX="console=tty0 crashkernel=auto net.ifnames=0 console=ttyS0 rootflags=pquota"

3. Identify the GRUB configuration file path.

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   Possible Locations

   /boot/grub2/grub.cfg
   /boot/efi/EFI/ubuntu/grub.cfg
   /boot/efi/EFI/debian/grub.cfg
   /boot/efi/EFI/redhat/grub.cfg
   /boot/efi/EFI/centos/grub.cfg
   /boot/efi/EFI/fedora/grub.cfg

4. Backup the existing GRUB configuration.

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   Backup Existing GRUB File

   sudo cp /boot/grub2/grub.cfg /boot/grub2/grub.cfg.backup

5. Regenerate the GRUB configuration.

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   Generate Updated GRUB Configuration

   sudo grub2-mkconfig -o /boot/grub2/grub.cfg

6. Reboot the system.

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   Reboot System

   sudo reboot

7. After reboot, verify the mount options again.

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   Check Mount Options

   sudo mount | grep "^/dev/nvme0n1p1"

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   Sample Output

   /dev/nvme0n1p1 on / type xfs (rw,relatime,seclabel,attr2,inode64,prjquota)

Filesystem on a Data Disk

If the filesystem is on a data disk:

1. Unmount the device.

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   Unmount the Device (Replace with Your Device)

   sudo umount /dev/nvme1n1

2. Mount the device with the pquota option.

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   Mount the Device with pquota

   sudo mount -o rw,pquota /dev/nvme1n1 /mnt/data

   pquota cannot be enabled using a remount operation.

3. Verify the mount options.

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   Verify pquota Mount Option

   sudo mount | grep "^/dev/nvme1n1"

4. Update /etc/fstab to persist the change.

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   Add pquota Option to /etc/fstab File

   UUID=9cff3d69-3769-4ad9-8460-9c54050583f9 /mnt/data xfs defaults,pquota 0 0

Enabling XFS Quota

Creating a StorageClass

Define a StorageClass with XFS quota support.

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: puls8-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

Advanced XFS Quota Configuration

Configure softLimitGrace and hardLimitGrace.

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: puls8-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

If no values are specified, defaults are softLimitGrace: "0%" and hardLimitGrace: "0%", restricting volume size to the PVC's requested storage.

Creating a PVC

Create a PVC using the StorageClass name.

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: local-hostpath-xfs
spec:
  storageClassName: puls8-hostpath-xfs
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 5Gi

Check the status of the PVC.

kubectl get pvc

NAME                  STATUS    VOLUME   CAPACITY   ACCESS MODES   STORAGECLASS           AGE
local-hostpath-xfs    Pending                                      puls8-hostpath-xfs   21s

Mounting the Volume

Mount the volume to the application pod container.

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

Verify that the XFS project quota is enforced.

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

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 [------]

Managing and Modifying XFS Quota

Identifying the BasePath Directory

Retrieve the BasePath directory.

kubectl describe sc <storageclass-name>

Locating the Node

Identify the node where the volume exists.

kubectl get pvc --namespace <namespace>

kubectl describe pv <pv-name>

Find the node.

kubectl get node -l 'kubernetes.io/hostname in (node-name)'

Modifying the XFS Quota Limits

Changing Quota Limits

Retrieve the current quota report.

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

Project quota on /var/openebs/local (/dev/nvme1n1)
                        Blocks
Project ID   Used   Soft   Hard Warn/Grace
---------- ---------------------------------
#0           0      0      0   00 [------]
#1           1G     2.0G   2.0G 00 [------]

Modify the soft and hard limits.

sudo xfs_quota -x -c 'limit -p bsoft=3G bhard=5G 1' /var/openebs/local

Verify the updated limits.

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

Project quota on /var/openebs/local (/dev/nvme1n1)
                        Blocks              
Project ID   Used   Soft   Hard Warn/Grace   
---------- --------------------------------- 
#0              0      0      0  00 [------]
#1             1G     3G     5G  00 [------]

Limitations

Quota resizing is not supported: If you need to adjust quotas, you must manually modify the soft and hard limits as shown above.

Learn More

• Raw Block Volume
• Volume Resize
• Etcd Migration Procedure