Planning the storage arrays

Prepare for disk storage configuration by planning for RAID arrays and volumes, according to the size of your IBM Spectrum Protect system.

You design storage arrays with size and performance characteristics that are suitable for one of the IBM Spectrum Protect server storage components, such as the server database or a storage pool. The storage planning activity must take account of drive type, RAID level, number of drives, the number of spare drives, and so on. In the solution configurations, storage groups contain internal-storage RAID arrays and consist of multiple physical disks that are presented as logical volumes to the system. When you configure the disk storage system, you create storage groups, or data storage pools, and then create storage arrays in the groups.

You create volumes, or LUNs, from the storage groups. The storage group defines which disks provide the storage that makes up the volume. When you create volumes, make them fully allocated. Faster disks types are used to hold the database volumes and active log volumes. Slower disk types can be used for the storage pool volumes, archive log, and database backup volumes. If you use a smaller disk storage pool to stage data, you might need to use faster disks to manage the daily workload performance for ingesting and migrating data.

Table 1 and Table 2 describe the layout requirements for storage groups and volume configuration.

Table 1. Components of storage group configuration
Component	Details
Server storage requirement	How the storage is used by the server.
Disk type	Size and speed for the disk type that is used for the storage requirement.
Disk quantity	Number of each disk type that is needed for the storage requirement.
Hot spare capacity	Number of disks that are reserved as spares to take over if disk failures occur.
RAID level	Level of RAID array that is used for logical storage. The RAID level defines the type of redundancy that is provided by the array, for example, 5 or 6.
RAID array quantity	Number of RAID arrays to be created.
DDMs per RAID array	How many disk drive modules (DDMs) are to be used in each of the RAID arrays.
Usable size per RAID array	Size that is available for data storage in each RAID array after accounting for space that is lost due to redundancy.
Total usable size	Total size that is available for data storage in the RAID arrays: `Quantity x Usable size`
Suggested storage group and array names	Preferred name to use for MDisks and MDisk groups.
Usage	Server component that uses part of the physical disk.

Table 2. Components of volume configuration
Component	Details
Server storage requirement	Requirement for which the physical disk is used.
Volume name	Unique name that is given to a specific volume.
Storage group	Name of the storage group from which the space is obtained to create the volume.
Size	Size of each volume.
Intended server mount point	Directory on the server system where the volume is mounted.
Quantity	Number of volumes to create for a specific requirement. Use the same naming standard for each volume that is created for the same requirement.
Usage	Server component that uses part of the physical disk.

Examples

Configuration examples for storage groups and volumes are available at the following link: Examples of worksheets for planning storage arrays. The examples show how to plan the storage for different server sizes. In the example configurations, there is a one-to-one mapping between disks and storage groups. You can download the examples and edit the worksheets to plan the storage configuration for your server.