Expanding storage pools

Virtual Storage Platform One SDS Block Storage Administrator Guide
Version
1.17.x
Audience
anonymous
Part Number
MK-24VSP1SDS002-04

When you configure a storage cluster, a storage pool is created. The storage pool is empty. Therefore, you must add drives to the storage pool.

CAUTION:

When you use Data at rest encryption in the cloud model for which BYOL is selected as a pricing model or in the bare metal model, verify that you already performed the procedure for enabling the encryption environment settings and the procedure for enabling the storage pool encryption settings described in Overview of Data at rest encryption before performing the procedures in this section. After you have completed the procedures described in this section, encryption environment settings and storage pool encryption settings cannot be changed.

To perform this operation, you need the Storage role. If you completed the procedure in Creating an initial user in the VSP One SDS Block Setup and Configuration Guide for the model you are using, a user is created in ServiceAdministrators. Because the Service and Storage roles are set for ServiceAdministrators, you can expand storage pools by using the user created in ServiceAdministrators. Perform the following procedures by using the user ID and password of this user as credentials for running commands.

To perform this operation, you need the Storage role. If setup is completed, a user is created in ServiceAdministrators. Because the Service and Storage roles are set for ServiceAdministrators, you can expand storage pools by using the user created in ServiceAdministrators. By using this user and user ID as credentials when running commands, perform the following procedures.

CAUTION:

  • If there is an operation that was performed before this procedure, confirm that the process is completed or terminated due to an error before performing this procedure. If the operation that was performed before this procedure is terminated due to an error, and the event log indicates the action that needs to be taken before this procedure, take that action, and then perform this procedure.

  • When a storage pool is expanded, the CPU usage of the storage node increases due to the internal processing. This might temporarily degrade host I/O performance.

Note:

(Cloud) In Multi-AZ configuration, in which a tiebreaker node has no drives, the verification targets in step 3 and step 7 do not include a tiebreaker node.

  • Required role: Storage

  1. Before you expand a storage pool, verify the logical capacity, free capacity, ID, rebuild capacity policy, and tolerable number of drive failures of the intended storage pool.

    If you use the CLI to specify a storage pool by name, check the name of the storage pool.

    REST API: GET /v1/objects/pools

    CLI: pool_list

  2. Change the rebuild capacity policy and tolerable number of drive failures as necessary to suit your operation.

    For details, see Editing storage pool settings.

    CAUTION:
    • If you change the rebuild capacity policy after expanding storage pools, sufficient rebuild capacity might not be secured. Therefore, if you want to change the rebuild capacity policy, do so before expanding storage pools.

    • (Cloud) When the Floating base license is applied, note the following:

      • In some cases, changing the tolerable number of drive failures exceeds the licensed capacity of the AWS License Manager license. Before changing the tolerable number of drive failures, see Estimating the storage pool capacity to confirm the consumed amount of a license (Cloud) to estimate the storage pool capacity after storage pool expansion, and then verify that the storage pool logical capacity is within the licensed capacity of the AWS License Manager license. Also, when estimating the required licensed capacity, round up the storage pool logical capacity to the unit of TiB.

        When multiple storage clusters share the AWS License Manager license, round up the storage pool logical capacity of each storage cluster to the unit of TiB first, and then sum the total to verify that the total logical capacity is within the licensed capacity of the AWS License Manager license.

        Example: If there are two storage clusters, one of which has 31.3 [TiB] and the other one has 47.7 [TiB] as storage pool logical capacity, round up those values to integers 32 [TiB] and 48 [TiB] respectively, and then sum the total as 80 [TiB].

        If the licensed capacity is insufficient, renew the license contract in AWS Marketplace.

      • The rebuild capacity policy cannot be changed from "Fixed."

  3. Verify the status of the storage node containing the drive you want to add.

    REST API: GET /v1/objects/storage-nodes

    CLI: storage_node_list

    If the status of the storage node is "Ready" or "RemovalFailed", go to step 3.

  4. Verify drive IDs.

    REST API: GET /v1/objects/drives

    CLI: drive_list

    Tip:

    A drive whose status is "Offline" is not incorporated into the storage pool. You can verify the drive status from drive information.

  5. Add drives to the storage pool.

    Run either of the following commands with the ID of the intended storage pool and the IDs of the drives to be added specified.

    If you use the CLI, you can specify a name instead of the ID of the storage pool.

    REST API: POST /v1/objects/pools/<id>/actions/expand/invoke

    CLI: pool_expand

    Verify the job ID which is displayed after the command is run.

    CAUTION:

    To perform other operations, verify that the storage pool has been expanded as described in step 7 before doing so.

  6. Verify the state of the job by specifying the job ID.

    REST API: GET /v1/objects/jobs/<jobId>

    CLI: job_show

    After running the command, if you receive a response indicating "Succeeded" as the state, the job is completed. Capacity allocation to storage controllers, which is internal processing, is performed within about two minutes after the job is completed. Upon completion of this process, the added capacity will be available for use.

    For the time required for capacity allocation processing to storage controllers, see Approximate processing time for allocating capacity to storage controllers (physical capacity) in this document.

  7. Obtain event logs to verify that the drives specified in step 5 can now be used as storage pool capacity.

    REST API: GET /v1/objects/event-logs

    CLI: event_log_list

    Wait for the event log KARS16020-I to output as many storage nodes as possible. Until then, you may not be able to perform other operations.

    If you get as many KARS16020-I event logs as the number of storage nodes, the storage pool has been expanded as specified.

    If event log KARS16046-I is output, the logical capacity (user-available capacity) could not be configured because the capacity of the specified drive or the number of drives is insufficient.

    (Bare metal) To configure the logical capacity, calculate the required capacity and expand the storage pool according to Expanding storage pools. For how to calculate the required capacity, see Capacity design (for HPEC 4D+1P) (Bare metal) , Capacity design (for HPEC 4D+2P), or Capacity design (for Mirroring).

    (Cloud) To configure the logical capacity, calculate the required capacity and expand the storage pool according to Expanding storage pools. For how to calculate the required capacity, see Capacity design (for HPEC 4D+2P) or Capacity design (for Mirroring).

    CAUTION:

    • If the write back mode with cache protection is enabled, you need to expand a storage pool for at least three drives for each storage node to configure logical capacity. Also, if you enable the write back mode with cache protection, you need to complete storage pool expansion for at least three drives for each storage node before enabling the mode. For details, see Enabling the write back mode with cache protection.

    • (Cloud) When the Floating base license is applied, adding drives might exceed the licensed capacity of the AWS License Manager license. To calculate the storage pool capacity after drive addition, see Estimating the storage pool capacity to confirm the consumed amount of a license (Cloud). Then, before adding drives, verify whether the storage pool logical capacity is within the licensed capacity of the AWS License Manager license. Also, when estimating the required licensed capacity, round up the storage pool logical capacity to the unit of TiB.

  8. Obtain information about the storage pool that has the newly-added drives.

    REST API: GET /v1/objects/pools

    CLI: pool_list

    Verify that the logical capacity and free capacity of the storage pool has increased as a result of adding the drives.

  9. (Bare metal) Back up the configuration information.

    Perform this step by referring to Backing up the configuration information (Bare metal).

    If you continue operations with other procedures, you must back up the configuration information after you have completed all operations.