Ranks — Main page

Use this page to view information for each rank in the selected storage unit.

Introduction

One or more arrays are combined to create a logically contiguous storage space called a rank.

Use the Refresh button to obtain current information. If no data is displayed, no ranks exist. You must create ranks before using this page.

Each rank number is linked to the associated rank properties information. Likewise, each data state entry is linked to the associated rank status information.

Note: If you are building a configuration in simulated mode or importing a real-time configuration into the simulated configurator, extent allocation per rank in an extent pool might not be the same. This means that the rank extent allocations that have been created in simulated mode or imported as part of a real-time configuration might not match the allocation as compared with applied and imported configurations and real-time configurations at the rank level, although the extent usage is equivalent. The real-time configuration extent allocation at the rank level will be configured appropriately.

Menu path

Real-time manager or Simulated manager > Configure storage > Ranks

Fields

Select storage unit

Specifies the storage unit that is being configured. You must have a storage unit that is configured to perform storage configuration tasks. This field is required.

Refresh button

Refreshes the information in the summary table. The last refresh date and time are also updated.

Last refresh

The most recent date and time of the information that is displayed in the summary table.

Select

Allows you to select a rank to perform additional actions.

Number

A unique identifier that consists of a storage unit identifier and a rank number (for example, R67).

Status (Real-time only)

The status indicates the current operational status of the rank. The links take you to the status page.

Normal — When the rank is in the following state:
- Data state: Normal
- Configuration state: Normal, Configuring, Unassigned, Reserved, or Deconfiguring
Attention — When the rank is in the following state:
- Data state: Degraded, Read only, or Repairing
  - Degraded — An array that is associated with this rank is in the Degraded state when one or more array members must be rebuilt. This occurs when a storage device has an array that is rebuilding or when a storage device has failed and would be rebuilding if there was an available spare.
  - Read-only — An array that is associated with this rank is in the Read-only state if one or more storage devices have failed, if there are insufficient spares to support all rebuild operations, and if continued write operations without redundancy might result in data loss.
  - Repairing — An array associated with this rank is in the Repairing state if the array was previously in the failed state and if initialization of the storage devices in the array is now in progress. The data state changes to Normal after the array initialization completes successfully. The data state changes to Failed if the action completes unsuccessfully and if there are no other available storage devices to replace those that could not be initialized.
- Configuration state: Configuration error
Failed — The rank is in the Failed state when an array that is associated with this rank is also in the Failed state.
Inaccessible — The rank is in the Inaccessible state when an array that is associated with this rank is also in the Inaccessible state.

Storage Type

The type of extent for which the rank is configured. Set to one of the following values:

Fixed block (FB) extents 1 GB. In fixed block architecture, the data (the logical volumes) are mapped over fixed-size blocks or sectors.
Count key data (CKD) extents CKD Mod 1. In count-key-data architecture, the data field stores the user data.

RAID

The supported or available RAID types (for example, RAID 5 and RAID 10).

Array

A unique identifier that consists of a storage unit identifier and an array number (for example, A44).

Extent Pool

The user specified nickname of the extent pool.

Total GB

The total amount of available usable storage in gigabytes (GB).

Used GB

The amount of allocated storage in this rank (for example, the extents used).

Actions

Create: Allows you to create a rank.
Delete: Allows you to delete the selected ranks. You cannot delete ranks that are in the Configuring or Deconfiguring states. If the selected ranks currently have volumes using storage on the rank, these volumes are deleted when you delete the ranks.
Modify: Allows you to modify the properties of the selected ranks. You cannot modify ranks that are in the Configuring or Deconfiguring states or ranks that have used extents.
Status: Displays the status of the selected ranks.
Operations: Allows you to reserve or release ranks.
Add to Extent Pool: Allows you to add the selected rank to an extent pool.
Remove from Extent Pool: Allows you to remove the selected rank from an extent pool.