mksestg

Parameters

-dev storage_image_ID

(Optional) The storage image ID, which consists of a value for manufacturer, machine type, and serial number. The -dev parameter temporarily overrides any defined value for devid for the current command. The storage image ID is required for the following situations:

• If you do not specify a fully qualified extent pool ID
• If you do not set the devid variable in your profile or through the setenv command
• If the HMC is aware of more than one storage image

-captype gb | blocks | cyl | mod1

(Optional) The unit type of capacity that is specified by the -vircap and the –repcap parameters. The following values are specified for each of these unit types:

gb

The capacity unit is gibibytes (GiB). This type is the default for fixed block storage when the -captype parameter is not specified. 1 GiB = 2 097 152 blocks.

This unit type can also be used with count key data (CKD) storage.

blocks

The capacity unit is blocks. This unit type is used only with fixed block storage. 1 block = 512 Bytes.

cyl

The capacity unit is cylinders. This unit type is used only with count key data (CKD) storage. 1 cylinder = 15 tracks.

mod1

The capacity unit is mod1. This unit type is used only with CKD storage (1 mod1 = 1113 cylinders). This type is the default for CKD storage when the -captype parameter is not specified.

-vircap capacity

(Optional) The amount of virtual capacity that can be allocated to all space-efficient logical volumes, including TSE and ESE volumes. All capacities must be designated as whole numbers. The capacity units are specified by the -captype parameter.

Note: Some storage system models require the ratio of virtual capacity to repository capacity to be at least 2:1.

-reptype tse | ese

(Optional) The type of repository that is affected by the repcap, reppercent, and repcapthreshold parameters.

Note: The default for the reptype parameter depends on the release level of your storage system. For example, starting with Release 8.0 storage systems, a TSE repository can no longer be created and is no longer supported. For Release 8.0 and later, if you do not specify the reptype parameter, the default is ESE.

For pre-Release 8.0 storage systems, if you do not specify the reptype parameter, the default is TSE.

tse

A track space-efficient physical repository.

ese

An extent space-efficient physical repository.

Note: An ESE repository is not required to create ESE volumes. By creating an ESE repository, you specify both a minimum capacity that is reserved for ESE volumes and a maximum capacity that is allowed for ESE volumes. By default, no ESE repository allows the entire pool to be used by any requester of that capacity whether it is for standard volumes, a TSE repository, virtual capacity (overhead), or ESE volumes. That is, the ESE volumes have 0% of the pool that is guaranteed, and the extent limit of the pool is allowed.

-repcapthreshold repository_threshold_percentage

(Optional) The minimum threshold percentage of the physical repository capacity that is available. When the percentage of the currently available repository capacity is less than this minimum percentage, notifications are sent and the repository capacity status is reported as exceeded. The default value is zero.

Notes:

1. Three thresholds for the repository generate notifications when their thresholds amounts are attained. Two of the three thresholds are set by the system and cannot be changed. They are set to 0% (full) and 15% (85% full). The third threshold is the user-defined threshold that is set here, and the repository capacity status is based on this threshold. When any of the three thresholds attain a threshold amount, a notification is sent for that particular threshold. No further notifications are sent until the repository capacity changes. If the repository capacity changes and remains above the threshold, another notification might be sent, but no more than one notification every 5 minutes. You must free capacity in the repository to stop the notifications. If the user-defined threshold is equal to one of the other two fixed thresholds, only one notification is sent, at most once every 5 minutes, for the two equivalent thresholds.
2. To verify that your storage complex is set up to send notifications, use the showsp command. If it is not set up, use the chsp command to set up notifications.

-repcap capacity

(Optional) The amount of physical capacity for the specified repository that you want to provision the virtual capacity of the space-efficient logical volumes. It is considered an error to create a repository that exists, but a single repository of each type is allowed in each extent pool. The repository type is specified with the -reptype parameter. All capacities must be designated as whole numbers. The capacity units are specified by the -captype parameter. You cannot specify the -repcap and -reppercent parameters at the same time.

Attention: TSE repositories can no longer be created starting with DS8900F Release 8.

An error occurs if you use this command to create a TSE/ESE repository when a TSE/ESE repository exists.

For TSE repositories:

• A TSE repository is required to create TSE volumes.
• All storage that is used to provision TSE volumes is physically allocated at the repository-creation time.
• The minimum repository capacity that can be created is as follows:
  • gb = 16 GiB
  • blocks = 33 554 432 blocks (equivalent to 16 GiB).
  • cyl = 17 808 cylinders.

For ESE repositories:

• An ESE repository is not required to create ESE volumes.
• All storage that is used to provision TSE volumes is physically allocated at the volume-creation time.
• The minimum repository capacity that can be created is 0 (zero) and prevents any ESE volume creation.
• Any existing ESE volumes become a part of the newly created ESE repository but remain otherwise unchanged. Any existing ESE volumes raise the minimum required repository capacity to be equal to capacity already allocated to provision those ESE volumes.

-reppercent percentage

(Optional) The amount of physical capacity for the specified repository that you want to provision the virtual capacity of the space efficient logical volumes. The physical capacity is specified as a percentage of the total virtual capacity. Creating a repository that exists is considered an error, but a single repository of each type is allowed in each extent pool. The repository type is specified with the -reptype parameter. You cannot specify the -repcap and -reppercent parameters at the same time. An error occurs if you use this command to create a TSE/ESE repository when a TSE/ESE repository exists.

This parameter is provided as a convenience. It is equivalent to using the –repcap parameter with a value determined by multiplying the total virtual capacity by the specified percentage and rounding up to the nearest whole number. However, this parameter is seldom used because the total virtual capacity is automatically increased as space-efficient volumes are created. Therefore, while the virtual capacity can be manually set to a higher value, the total virtual capacity is equal to the sum of all the capacities of the space-efficient volumes.

Note: Some storage system models require the ratio of virtual capacity to repository capacity to be at least 2:1. On systems with this requirement, the effective maximum percentage is 50%. In many cases, a value of 20% of the virtual capacity is a good value. However, less than 20% of virtual capacity might significantly degrade performance.

-wait

(Optional) The command will be delayed until after the space efficient storage is created, configured, and in a Normal state. If an error condition is detected while waiting, the command returns and reports an error.

extentpool_ID | -

(Required) The extent pool that is used to provision the extents that are used by this space efficient storage. For example, P111. If you use the dash (-), the specified value is read from standard input. You cannot use the dash (-) while you are in the DS CLI interactive command mode.