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(Recommended) Creating an SFS Turbo Subdirectory Using a Dynamic PV

When an SFS Turbo volume is mounted to a workload container, the root directory is mounted to the container by default. However, the minimum capacity of an SFS Turbo volume is 500 GiB, which exceeds the capacity required by most workloads, leading to a waste of storage resources. CCE enables efficient utilization of storage capacity by creating SFS Turbo subdirectories dynamically when you create a PVC. If your Everest version is 2.4.73 or later, you can configure the capacities of these subdirectories. This allows multiple workloads to share the SFS Turbo file system.

Prerequisites

  • You have created a cluster and installed the CCE Container Storage (Everest) add-on of v2.3.23 or later in the cluster.
  • To create a cluster using commands, ensure kubectl is used. For details, see Accessing a Cluster Using kubectl.
  • You have created an available SFS Turbo file system, and the SFS Turbo file system and the cluster are in the same VPC.

Notes and Restrictions on Subdirectory Quotas

  • If the subdirectory quota is less than 1 GiB, it is automatically set to 1 GiB. The maximum quota cannot exceed the capacity of the target SFS Turbo file system. The minimum scale-out step is 1 GiB, and capacity reduction is not allowed.
  • Once a subdirectory quota is configured, it cannot be canceled.
  • The number of files or subdirectories in a file system is determined by the quota capacity (in KB) divided by 16. The upper limit is set at 1 billion and cannot be changed by users.

Dynamically Creating an SFS Turbo Subdirectory on the Console

  1. Log in to the CCE console and click the cluster name to access the cluster console.
  2. Choose Storage in the navigation pane. In the right pane, click the PVCs tab. Click Create PVC in the upper right corner. In the dialog box displayed, configure PVC parameters.

    Parameter

    Description

    PVC Type

    In this example, select SFS Turbo.

    PVC Name

    Enter the PVC name, which must be unique in a namespace.

    Creation Method

    Select New subdirectory.

    Storage Classes

    Choose csi-sfsturbo. You can customize a StorageClass and configure its reclaim policy and binding mode. For details, see Creating a StorageClass Using the CCE Console.

    Access Mode

    SFS Turbo volumes support only ReadWriteMany, indicating that a storage volume can be mounted to multiple nodes in read/write mode. For details, see Volume Access Modes.

    SFS Turbo

    Click Select SFS Turbo. On the displayed page, select the SFS Turbo file system that meets your requirements and click OK.

    Subdirectory

    Enter the absolute path of a subdirectory, for example, /a/b.

    Subdirectory Reclaim Policy

    Determine whether to retain subdirectories when a PVC is deleted.

    • Retain: If a PVC is deleted, the PV will be deleted, but the subdirectories associated with the PV will be retained.
    • Delete: After a PVC is deleted, the PV and its associated subdirectories will also be deleted.
      NOTE:

      When a subdirectory is deleted, only the absolute path of the subdirectory configured in the PVC will be deleted. The upper-layer directory will not be deleted.

    Subdirectory Capacity

    • Not limited: The subdirectory capacity is not limited.
    • Limited: The subdirectory capacity is limited.

    Capacity

    The maximum capacity of the subdirectory, in GiB. This parameter is available only when the subdirectory capacity limit is enabled.

  3. Click Create to create a PVC and a PV.

    You can choose Storage in the navigation pane and view the created PVC and PV on the PVCs and PVs tab pages, respectively.

Dynamically Creating an SFS Turbo Subdirectory Using kubectl

  1. Use kubectl to access the cluster.
  2. Create the pvc-sfsturbo-subpath.yaml file.

    apiVersion: v1
    kind: PersistentVolumeClaim
    metadata:
    name: pvc-sfsturbo-subpath # PVC name
    namespace: default
    annotations:
    everest.io/volume-as: absolute-path # An SFS Turbo subdirectory is used.
    everest.io/sfsturbo-share-id: <sfsturbo_id> # SFS Turbo ID
    everest.io/path: /a # Subdirectory that is automatically created, which must be an absolute path
    everest.io/reclaim-policy: retain-volume-only # When a PVC is deleted, the PV will be deleted, but the subdirectories associated with the PV will be retained.
    everest.io/csi.enable-sfsturbo-dir-quota: "true" # Status of quota limit
    spec:
    accessModes:
    - ReadWriteMany # ReadWriteMany must be selected for SFS Turbo.
    resources:
    requests:
    storage: 10Gi # For SFS Turbo subdirectory PVCs, this configuration specifies the capacity of a subdirectory when quota limit is enabled. In other scenarios, it is meaningless and only used for verification (the value cannot be empty or 0).
    storageClassName: csi-sfsturbo # StorageClass name of the SFS Turbo file system
    Table 1 Key parameters

    Parameter

    Mandatory

    Description

    everest.io/volume-as

    Yes

    The value is fixed at absolute-path, indicating that a dynamically created SFS Turbo subdirectory is used.

    everest.io/sfsturbo-share-id

    Yes

    SFS Turbo ID

    How to obtain: Log in to the CCE console, choose Service List > Storage > Scalable File Service, and select SFS Turbo. In the list, click the name of the target SFS Turbo file system. On the details page, copy the content following ID.

    everest.io/path

    Yes

    Subdirectory that is automatically created, which must be an absolute path.

    everest.io/reclaim-policy

    Yes

    Whether to retain subdirectories when deleting a PVC. This parameter must be used with PV Reclaim Policy. This parameter is available only when the PV reclaim policy is Delete. Options:

    • retain-volume-only: If a PVC is deleted, the PV will be deleted, but the subdirectories associated with the PV will be retained.
    • delete: After a PVC is deleted, the PV and its associated subdirectories will also be deleted.
      NOTE:

      When a subdirectory is deleted, only the absolute path of the subdirectory configured in the PVC will be deleted. The upper-layer directory will not be deleted.

    everest.io/csi.enable-sfsturbo-dir-quota

    No

    Whether to enable quota limit for a subdirectory. If the value is set to true, the limit is enabled. If the value is empty or set to any other value, the limit is disabled.

    storage

    Yes

    Requested capacity in the PVC, in Gi.

    • When subdirectory capacity limit is enabled (everest.io/csi.enable-sfsturbo-dir-quota is set to true), storage indicates the capacity of a subdirectory, and its value must be an integer.

      If storage is set to a decimal, the value will be rounded up automatically. For example, if storage is set to 10.1Gi, an 11-GiB subdirectory will be created.

    • If a subdirectory capacity is not limited, this parameter is meaningless and only used for verification. You can set this parameter to a fixed value 10Gi.

  3. Run the following command to create a PVC:

    kubectl apply -f pvc-sfsturbo-subpath.yaml