Defining and attaching replicated storage resources (IBM FlashSystem A9000 and IBM FlashSystem A9000R only)

For IBM FlashSystem® A9000 and IBM FlashSystem A9000R mirrored storage systems and services, you can define primary and secondary storage resources to be used for data replication.

Before you begin

Verify that:
  • Primary and secondary storage systems were added to Spectrum Connect.
  • A storage service to use the replicated storage resources has the replication capability enabled.
  • A target has been defined on a storage system for the management domain to be used by the paired pool. The storage system credentials must be valid for both primary and secondary pool domains.

About this task

You can define paired storage resource (pool), which contains a primary (source) pool and secondary (target) pool. Then, the paired pool is attached to a replicated service. This process will create a storage volume and its mirror on the target pool. You can use the IBM® Storage Enhancements for VMware vSphere Web Client to provision the volume as a part of a consistency group. The primary and secondary pools reside on the source and target storage systems, which can be located at different sites.

Procedure

  1. On the Spaces/Storage Services pane, select the storage space from which you want to choose storage services.
    The available services that reside on the selected storage space are immediately displayed.
  2. Click on a service with replication capabilities to which you want to attach the resources.
    The service color changes to blue to indicate selection.
  3. On the Storage Systems pane, right-click a compatible storage system on which you want to define a new resource, and then select Add Resource.
    The Add New Resource dialog box is displayed.

    You can choose to create a new paired resource, or select existing ones.

    Figure 1. Add New Resource for replicated service dialog box, Create New option
    This image shows the Add New Resource dialog for replicated service dialog box.
    Figure 2. Add New Resource for replicated service dialog box, Choose Existing option
    This image shows the Add New Resource dialog for replicated service dialog box.
  4. In the Add New Resource dialog box, enter configuration parameters for a new resource (paired pool). See table below for details.
    Table 1. Paired pool parameters
    Parameter Description and values
    Name Alphanumeric string for identification of the replication relationship. The name must not contain spaces.
    Create new New primary and secondary storage resources to be created for the paired pool.
    Choose existing Existing primary and secondary storage resources to be selected for the paired pool.
    Array A storage system to include the primary or secondary storage resource.
    Domain Management domain of the pool on the storage systems,.

    Configuration considerations

    To use management domains, verify that:
    • Domains are already defined on your storage system.
    • Default credentials of a storage admin user are assigned to the domain.
    Size Storage resource size in GiB. The size of the replicated pool cannot be larger than the size of the smallest pool of the paired resources (primary or secondary). When you select existing pools for replication, the pool size cannot be changed.
    Over-provisioning Percentage of over-provisioned storage space on the service, defining the ratio between logical and physical storage capacity on XIV® storage systems. For example, when configured to 100, it sets a 1:1 ratio between the two values, while a value of 200 defines the logical capacity (soft size) to be twice the physical capacity (hard size).

    Configuration considerations

    The recommended over-provisioning value for a service with IBM Real-time Compression is 200%.

    The XIV utilizes thin provisioning for all VM configuration volumes. When creating a regular VM on an XIV disk, you can choose the provisioning mode, according to your application requirements.

    For other cases, you can choose any value:
    • 100%, if you do not want to utilize thin provisioning.
    • Above 100%, if you want to take a risk of allocating resources that the XIV storage system may not have.

    In addition, when utilizing the over-provisioning, XIV storage systems must be also configured to allow support for this feature. When used with the XIV domains, the domain must be also configured with matching soft and hard capacity settings.

    Important

    The managed domain that you created cannot be used for traditional volumes without virtualization. You must create a separate regular domain for them. This domain must have the same user and the ESXi hosts that you intend to manage. However, you need to create a separate storage resource and a new service on the regular domain via Spectrum Connect for subsequent use by the vWC.

    The over-provisioning is relevant for XIV storage systems only.

    Configuration examples

    • Storage pools in a regular service with over-provisioning at 100% are created as thick pools.
    • Storage pools in a regular service with over-provisioning at 150% are created as thin pools. If a hard pool size is 500 GiB, its soft size is 750 GiB.
    Snapshot reserve Percentage of storage space on the service reserved for snapshots.
  5. Click Add.
    The storage resource is created on the storage system and attached to the service. The resource color changes to blue to indicate the successful attachment.

    You can check pool pairing by hovering your mouse pointer over a primary or secondary storage resource. The paired pool colors change to purple and a coupling line is displayed to indicate the connection.

    Figure 3. Paired pools
    This image shows the paired pools.

    The resources defined on the system before the system was attached to Spectrum Connect, can be allocated to a service by selecting the service and clicking an unattached resource.

    A storage service provides indication for the allocated and used storage space.
    • Allocated – amount of storage space available on all pools connected to the service.
    • Used – amount of storage space used by all storage elements connected to the service (datastores, servers, etc).
  6. You can display detailed information for all storage resources defined on a storage system by switching to the table view.
    The System Storage Resources table is displayed.
    Figure 4. Storage Resources table
    This image shows the System Storage Resources table.
    The table lists all storage resources defined on the storage system, including their sizes, free and used storage space, and a service that the resource is attached to. When you click on a storage resource row to select it, you can complete the following:
    • Click the Attach/Delegate button to attach the storage resource to a previously selected storage service.
    • Click the Detach/Cancel Delegation button to detach the storage resource from a previously selected storage service.
    • Right-click and select Modify to resize the resource or remove it.
    • Right-click and select Unlink to break the replication connection between the storage resources of the paired pool. The primary and secondary pools themselves remain intact.
  7. You can display detailed information for all storage resources attached to a service on a storage system by right-clicking the service on which you want zoom, and then selecting View Resources.
    The Service Storage Resources table is displayed.
    Figure 5. Service Storage Resources table
    This image shows the Service Storage Resources table.
    The table lists all storage resources attached to the storage service, including their sizes, free and used storage space and a system that the resource was created on. When you click on a storage resource row to select it, you can complete the following:
    • Click the Resource Detach button to detach the storage resource from a storage service.
    • Click the Resource Settings button to resize the resource or remove it.
    • Click the Remove button to delete a pool.