DEFINE STGPOOL (Define a primary storage pool for offloading data to tape)

Privilege class

To issue this command, you must have system privilege.

Parameters

pool_name (Required)

Specifies the name of the storage pool to be defined. The name must be unique, and the maximum length is 30 characters.

POoltype=PRimary

Specifies that you want to define a primary storage pool. This parameter is optional. The default value is PRIMARY.

STGType=COLDDATACache

Specifies the type of storage. This parameter is optional and the default value is COLDDATACACHE. To define a storage pool of type COLDDATACACHE, you must specify COLDDATACACHE.

COLDDATACache

Specifies that the storage pool is used for offload operations to tape. Only data from object clients can be stored in this type of storage pool.

Tip: Cold-data-cache storage pools cannot be specified as next storage pools of any storage pool, including other storage pools of type COLDDATACACHE.

DESCription

Specifies a description of the storage pool. This parameter is optional. The maximum length of the description is 255 characters. Enclose the description in quotation marks if it contains any blank characters.

ACCess

Specifies how client nodes and server processes (such as migration and reclamation) can access files in the storage pool. This parameter is optional. The default value is READWRITE. You can specify the following values:

READWrite

Specifies that client nodes and server processes can read and write to files stored on volumes in the storage pool.

READOnly

Specifies that client nodes can only read files from the volumes in the storage pool.

Server processes can move files within the volumes in the storage pool. However, no new write operations are permitted to volumes in the storage pool from volumes outside the storage pool.

If this storage pool was specified as a subordinate storage pool (with the NEXTSTGPOOL parameter) and is defined and ACCESS=READONLY, the storage pool is skipped when server processes attempt to write files to the storage pool.

UNAVailable

Specifies that client nodes cannot access files stored on volumes in the storage pool.

Server processes can move files within the volumes in the storage pool and can also move or copy files from this storage pool to another storage pool. However, no new write operations are permitted to volumes in the storage pool from volumes outside the storage pool.

If this storage pool was specified as a subordinate storage pool (with the NEXTSTGPOOL parameter) and ACCESS=UNAVAILABLE, the storage pool is skipped when server processes attempt to write files to the storage pool.

MAXSIze

Specifies the maximum size for a physical file that the server can store in the storage pool. This parameter is optional. The default value is NOLIMIT. You can specify one of the following values:

NOLimit

Specifies that there is no maximum size limit for physical files stored in the storage pool.

maximum_file_size

Limits the maximum physical file size. Specify an integer in the range 1 - 999999, followed by a scale factor. For example, MAXSIZE=5G specifies that the maximum file size for this storage pool is 5 gigabytes. Specify one of the following scale factors:

Scale factor	Meaning
K	kilobyte
M	megabyte
G	gigabyte
T	terabyte

The client estimates the size of files that are sent to the server. The client estimate is used rather than the actual amount of data that is sent to the server. Client options, such as data deduplication, compression, and encryption, can cause the amount of data that is sent to the server to differ from the size estimate. For example, the compression of a file might be smaller in size than the estimate, thus sending less data than the estimate. Furthermore, a binary file might be larger in size after the compression processing, thus sending more data than the estimate.

When the physical size of the storage pool exceeds the MAXSIZE parameter, the following table shows where files are typically stored.

Table 1. The location of a file according to the file size and the pool that is specified

File size	Pool specified	Result
Exceeds the maximum size	No pool is specified as the next storage pool in the hierarchy.	The server does not store the file.
	A pool is specified as the next storage pool in the hierarchy.	The server stores the file in the next storage pool that can accept the file size.

Tip: If you also specify the NEXTSTGPOOL parameter, define one storage pool in your hierarchy to have no limit on the maximum file size by specifying the MAXSIZE=NOLIMIT parameter. When you have at least one pool with no size limit, you ensure that no matter what its size, the server can store the file.

For multiple files that are sent in a single transaction, the server considers the size of the transaction to be the file size. If the total size of all files in the transaction is larger than the maximum size limit, the server does not store the files in the storage pool.

If the file size from an object client node exceeds the MAXSIZE parameter, file backup will fail.

Restriction:

This parameter is not available for storage pools that use the following data formats:

• NETAPPDUMP
• CELERRADUMP
• NDMPDUMP

NEXTstgpool

Specifies a primary storage pool to which files are migrated. You cannot migrate data from a sequential-access storage pool to a random-access storage pool. This parameter is optional.

Restrictions: The following restrictions apply when you specify the NEXTSTGPOOL parameter for cold-data-cache storage pools:

• The next storage pool must use a tape-based device class.
• Data deduplication must not be enabled for the next storage pool.
• The next storage pool of a cold-data-cache storage pool cannot have its own next storage pool.

If the newly-defined storage pool does not have a next storage pool, the server cannot migrate files from the new storage pool and cannot store files that exceed the maximum size for this storage pool in another storage pool.

If the next storage pool has insufficient space, data is not migrated to that storage pool. In this case, the server issues a message and the transaction fails.

For next storage pools with a device type of FILE, the server completes a preliminary check to determine whether sufficient space is available. If space is not available, the server skips to the next storage pool in the hierarchy. If space is available, the server attempts to store data in that pool. However, if space is no longer available when the operation takes place, the operation fails.

Restrictions:

• To ensure that you do not create a chain of storage pools that leads to an endless loop, specify at least one storage pool in the hierarchy with no value.
• If you specify a sequential-access pool as the next storage pool, the pool must be in either NATIVE or NONBLOCK data format.
• Do not specify a directory-container or cloud-container storage pool.
• Do not use this parameter to specify a storage pool for data migration.
• This parameter is not available for storage pools that use the following data formats:
  • NETAPPDUMP
  • CELERRADUMP
  • NDMPDUMP

DIRectory

Specifies one or more directories that can be used for the cold-data-cache storage pool. If you specify STGTYPE=COLDDATACACHE, you must specify the DIRECTORY parameter because one or more directories are required for the automatic creation of the device class. You can update the device class at a later point by issuing the UPDATE DEVCLASS command.

Important: This parameter is required only if you specify STGTYPE=COLDDATACACHE.

MIGPRocess

Specifies the number of parallel processes to use for migrating the files from the volumes in this storage pool. This parameter is optional. Enter a value in the range 1 - 999. The default value is 1.

When calculating the value for this parameter, consider the number of sequential storage pools that will be involved with the migration, and the number of logical and physical drives that can be dedicated to the operation. To access a sequential-access volume, IBM Spectrum Protect uses a mount point and, if the device type is not FILE, a physical drive. The number of available mount points and drives depends on other IBM Spectrum Protect and system activity and on the mount limits of the device classes for the sequential-access storage pools that are involved in the migration.

For example, suppose that you want to simultaneously migrate the files from volumes in two primary sequential-access storage pools and that you want to specify three processes for each of the storage pools. The storage pools have the same device class. Assuming that the storage pool to which files are being migrated has the same device class as the storage pool from which files are being migrated, each process requires two mount points and, if the device type is not FILE, two drives. (One drive is for the input volume, and the other drive is for the output volume.) To run six migration processes simultaneously, at least 12 mount points and 12 drives are required. The device class for the storage pools must have a mount limit of at least 12.

If the number of migration processes you specify is more than the number of available mount points or drives, the processes that do not obtain mount points or drives will wait for mount points or drives to become available. If mount points or drives do not become available within the MOUNTWAIT time, the migration processes will end. For information about specifying the MOUNTWAIT time, see DEFINE DEVCLASS (Define a device class).

The IBM Spectrum Protect server will start the specified number of migration processes regardless of the number of volumes that are eligible for migration. For example, if you specify 10 migration processes and only 6 volumes are eligible for migration, the server will start 10 processes and 4 of them will finish without processing a volume.

Tip: When you specify this parameter, consider whether the simultaneous-write function is enabled for server data migration. Each migration process requires a mount point and a drive for each copy storage pool and active-data pool that is defined to the target storage pool.

Restriction: This parameter is not available for storage pools that use the following data formats:

• NETAPPDUMP
• CELERRADUMP
• NDMPDUMP

REMOVERESToredcopybeforelifetimeend

Specifies that data that is restored to the cold-data-cache storage pool because of a request from IBM Spectrum Protect Plus can be deleted before the specified expiration date for that data. This parameter is relevant if the occupancy of the cold-data-cache storage pool is nearing capacity. This parameter is optional. The default value is NO.

Data is eligible for early deletion according to a defined time threshold, specified in days, according to the following sequence:

1. Data that was copied to the cold-data-cache storage pool and read more than a specified number of days ago. The oldest data is deleted first.
2. Data that was copied to the cold-data-cache storage pool more than a specified number of days ago. The most recently copied data is deleted first.

YES

Specifies that data that is restored to the cold-data-cache storage pool because of request from the object client can be deleted from the storage pool before the specified expiration period is reached. Only data that is eligible for early deletion according to the defined thresholds and criteria is deleted.

NO

Specifies that data that is restored to the cold-data-cache storage pool because of a request from the object client is not subject to deletion when the storage-pool occupancy nears capacity.

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