Tailor your storage class configuration with mount options

Leverage mount options for tailored storage control with the CSI Plugin.

Overview

The CSI Plugin empowers you with mount options, allowing you to customize how WekaFS volumes are presented to pods. This enables granular control over storage behavior, optimizing performance and data management for containerized workloads.

Mount options are key-value pairs specified during volume mounting that modify the default filesystem or storage provider behavior. These settings influence caching, data integrity, filesystem limits, and more.

When to use mount options:

• Tailor performance: Optimize caching strategies for read-heavy or write-intensive workloads (noatime, readcache).

• Enhance data integrity: Enforce data consistency and reliability (example: sync).

• Customize behavior: Adjust settings like filesystem size limits for specific use cases (example: fstype).

• Troubleshoot issues: Fine-tune settings to resolve performance bottlenecks or compatibility problems.

Standard mount options and use cases

The CSI Plugin supports all standard mount options except the read-only (ro) option. The following table briefly lists the supported mount options for convenience.

Option	Description	Use cases
sync	Ensure data is written to disk before mount	Database workloads requiring high data integrity
noatime	Disable write timestamp updates	Reduce write amplification, improve performance
nodev	Disallow device nodes	Security-sensitive environments
noexec	Disallow program execution	Security-focused deployments
atime	Enable access time recording	Monitor file access patterns
diratime	Enable directory access time recording	Track directory access time
relatime	Update access and modification times relative to stat time	Reduce write amplification, improve performance
data=ordered	Ensure sequential writes are flushed to disk immediately	Databases requiring strict write ordering
fstype	Specify the filesystem type	Use case-specific filesystems (examples: XFS, ext4)

Set custom mount options with CSI Plugin

This example procedure demonstrates how to set custom mount options using the WEKA CSI Plugin.

Prerequisites:

• The Kubernetes environment is set up and accessible.

• The kubectl command-line tool is installed and configured.

Procedure:

1. Create StorageClass:

   a. Open or create a YAML file for your StorageClass definition (for example, storageclass-wekafs-mountoptions.yaml).

   b. Add the following content to define the StorageClass with custom mount options:

   apiVersion: storage.k8s.io/v1
   kind: StorageClass
   metadata:
     name: storageclass-wekafs-mountoptions
   provisioner: csi.weka.io
   parameters:
     mountOptions: "rw,relatime,readcache,noatime,readahead_kb=32768,dentry_max_age_positive=1000,dentry_max_age_negative=0"

   c. Apply the StorageClass using the following command:

   kubectl apply -f storageclass-wekafs-mountoptions.yaml

2. Create CSI secret: a. Execute the following command to create a CSI secret named csi-wekafs-api-secret (located in ../common/csi-wekafs-api-secret.yaml):

   kubectl apply -f ../common/csi-wekafs-api-secret.yaml

   This step ensures that the necessary credentials are available for the CSI Plugin.

3. Provision a new volume:

   Apply the StorageClass to provision a new volume. Use the following command:

   kubectl apply -f <FILE>.yaml

   • Replace <FILE> with the path to your YAML file containing the Persistent Volume Claim (PVC) definition.

4. Create application:

   a. Create an application manifest file (for example, csi-app-fs-mountoptions.yaml) or use an existing one.

   b. In the manifest, specify the PVC with the custom mount options:

   apiVersion: apps/v1
   kind: Deployment
   metadata:
     name: csi-app-fs-mountoptions
   spec:
     replicas: 1
     selector:
       matchLabels:
         app: csi-app-fs-mountoptions
     template:
       metadata:
         labels:
           app: csi-app-fs-mountoptions
       spec:
         containers:
         - name: csi-app-fs-mountoptions
           image: <YOUR_IMAGE>
           volumeMounts:
           - mountPath: "/data"
             name: wekafs-volume
         volumes:
         - name: wekafs-volume
           persistentVolumeClaim:
             claimName: pvc-wekafs-fs-mountoptions

   • Replace <YOUR_IMAGE> with the desired container image.

   c. Deploy the application:

   kubectl apply -f csi-app-fs-mountoptions.yaml

5. Attach and validate:

   Attach to the application pod:

   kubectl exec csi-app-fs-mountoptions -- mount -t wekafs

   b. Verify that the output resembles to the following example:

   csivol-pvc-15a45f20-Z72GJXDCEWQ5 on /data type wekafs (rw,relatime,readcache,noatime,readahead_kb=32768,dentry_max_age_positive=1000,dentry_max_age_negative=0)
   

The acl mount option is used internally by the WEKA CSI Plugin and cannot be set via StorageClass configuration

Mount options are initialized on the Persistent Volume (PV) during creation and will stick to the PV during its whole lifetime. Mount options cannot be changed for existing persistent volumes. Hence, it is recommended to carefully consider required mount options prior to creation of long-living persistent volumes.