Creating an HDFS Storage Pool

This section describes how to create a storage pool from which application servers can use storage space.

Context

Only one storage pool whose Service Type is HDFS can be created, and the storage pool can contain one or multiple disk pools.

Procedure

  1. Choose Cluster > Storage Pool.
  2. Click Create.

    The Create Storage Pool page is displayed.

  3. In the Basic Information area, configure basic information for the storage pool.

    Table 1 describes related parameters.

    Table 1 Storage pool parameters

    Parameter

    Description

    Storage Pool Name

    Indicates the name of a storage pool.

    NOTE:
    • The name must be unique.
    • The name can contain only letters, digits, underscores (_), and hyphens (-).
    • The name contains 1 to 64 characters.

    Service Type

    Indicates the service type of a storage pool. Select HDFS.

    Storage Pool Type

    Indicates the type of the storage pool. When Service Type is set to HDFS, only Common is supported.

    Security Level

    Indicates the security level of a storage pool. When Service Type is set to HDFS, only Node is supported.

    Redundancy Policy

    Indicates the redundancy policy of a storage pool. When Service Type is set to HDFS, only EC is supported.

    EC

    Indicates the EC redundancy policy of the storage pool. The value is in the format of +M or +M:1, where M indicates the number of parity fragments. Currently, +2:1, +2, +3:1, +3, +4:1, and +4 are supported.

  4. In the Disk Pool area, create a disk pool.

    1. Click Create.

      The Create Disk Pool page is displayed.

    2. Set basic parameters for the disk pool. Table 2 describes related parameters.
      Table 2 Disk pool parameters

      Parameter

      Description

      Disk Pool Name

      Indicates the name of the disk pool.

      NOTE:
      • The name must be unique.
      • The name can contain only letters, digits, underscores (_), and hyphens (-).
      • The name contains 1 to 64 characters.

      Main Storage

      Indicates the main storage type of the disk pool. Possible options are SAS, SATA, SSD card or NVMe SSD, and SSD.

      NOTE:

      Meanings of the options are as follows:

      • SAS: SAS HDDs
      • SATA: SATA HDDs
      • SSD card or NVMe SSD: PCIe SSD (NVMe) cards or NVMe SSDs
      • SSD: SAS SSDs and SATA SSDs

      Cache

      Indicates the cache type of the disk pool. Possible options are SSD card or NVMe SSD and SSD.

      Max. Main Storage Media per Node

      Indicates the maximum number of storage disks that can be used by a single node to store user data. The value of this parameter determines the allocation of cache and compute resources on the node. Set this parameter based on site requirements.

      To ensure that cache resources can be allocated to newly added main storage disks in the case of capacity expansion, you are advised to set this parameter based on the total number of main storage disks after capacity expansion.

      • If the value is too small, newly added main storage disks cannot be allocated with cache resources. Cache resources can be allocated to newly-added main storage disks only after the capacities of both main storage disks and cache disks are expanded.
      • If the value is too large, extra cache resources are reserved. As a result, cache resources cannot be fully utilized to improve read/write performance.

      If you select Default, the system automatically determines the value based on the number of selected main storage disks. Assume that the number of selected main storage disks is N:

      • If N ≤ 12, a single node supports a maximum of 12 main storage disks.
      • If 12 < N ≤ 24, a single node supports a maximum of 24 main storage disks.
      • If 24 < N ≤ 36, a single node supports a maximum of 36 main storage disks.

      Tier Grade

      Indicates the tier grade of a disk pool. You can configure a tiering policy to store different files in different grades of disk pools.

      NOTE:

      If you select Default, when Main Storage is set to SSD or SSD card or NVMe SSD, the tier grade of the disk pool is Hot. When Main Storage is set to SAS, the tier grade of the disk pool is Warm. When Main Storage is set to SATA, the tier grade of the disk pool is Cold.
    3. Click Add. On the Choose Node page that is displayed, select the nodes and disks for creating a disk pool.

      You can select one or more added nodes and disks and click Remove to remove them.

    4. Click OK and confirm your operation as prompted.

  5. Click Create.
  6. Confirm your operation as prompted.
Parent topic: Configuring the HDFS Service