Use the LTO device class when you are using LTO tape devices.
To issue this command, you must have system privilege or unrestricted storage privilege.
>>-UPDate DEVclass--device_class_name---------------------------> >--+--------------------------+---------------------------------> '-LIBRary--=--library_name-' >--+-----------------------------+------------------------------> '-LBProtect--=--+-READWrite-+-' +-WRITEOnly-+ '-No--------' >--+--------------------------+--+----------------------+-------> '-FORMAT--=--+-DRIVE-----+-' '-ESTCAPacity--=--size-' +-ULTRIUM---+ +-ULTRIUMC--+ +-ULTRIUM2--+ +-ULTRIUM2C-+ +-ULTRIUM3--+ +-ULTRIUM3C-+ +-ULTRIUM4--+ +-ULTRIUM4C-+ +-ULTRIUM5--+ +-ULTRIUM5C-+ +-ULTRIUM6--+ '-ULTRIUM6C-' >--+-----------------------------------+------------------------> '-PREFIX--=--+-ADSM---------------+-' '-tape_volume_prefix-' >--+----------------------------+--+-----------------------+----> '-MOUNTRetention--=--minutes-' '-MOUNTWait--=--minutes-' >--+---------------------------+--------------------------------> '-MOUNTLimit--=--+-DRIVES-+-' +-number-+ '-0------' >--+----------------------------------------------+------------>< | (1) (2) | '-------------DRIVEEncryption--=--+-ON-------+-' +-ALLOW----+ +-EXTERNAL-+ '-OFF------'
Specifies whether logical block protection is used to ensure the integrity of data stored on tape. When LBPROTECT is set to READWRITE or to WRITEONLY, the server uses this feature of the tape drive for logical block protection and generates cyclic redundancy check (CRC) protection information for each data block written on tape. The server also validates the CRC protection information when data is read from the tape.
When the LBPROTECT parameter is set to READWRITE, you do not have to specify the CRCDATA parameter in a storage pool definition because logical block protection provides better protection against data corruption.
If you are considering mixing different generations of LTO media and drives, be aware of the following restrictions.
Drives | Generation 1 media | Generation 2 media | Generation 3 media | Generation 4 media | Generation 5 media | Generation 6 media |
---|---|---|---|---|---|---|
Generation 1 | Read and write | n/a | n/a | n/a | n/a | n/a |
Generation 2 | Read and write | Read and write | n/a | n/a | n/a | n/a |
Generation 3 1 | Read only | Read and write | Read and write | n/a | n/a | n/a |
Generation 4 2 | n/a | Read only | Read and write | Read and write | n/a | n/a |
Generation 5 3 | n/a | n/a | Read only | Read and write | Read and write | n/a |
Generation 6 4 | n/a | n/a | n/a | Read only | Read and write | Read and write |
1 In a library with a Generation 3 drive, all Generation 1 scratch volumes must be checked out, and all Generation 1 storage pool volumes must be updated to read-only. 2 In a library with a Generation 4 drive, all Generation 2 scratch volumes must be checked out, and all Generation 2 storage pool volumes must be updated to read-only. 3 In a library with a Generation 5 drive, all Generation 3 scratch volumes must be checked out, and all Generation 3 storage pool volumes must be updated to read-only. 4 In a library with a Generation 6 drive, all Generation 4 scratch volumes must be checked out, and all Generation 4 storage pool volumes must be updated to read-only. |
Format | Estimated capacity | Description |
---|---|---|
DRIVE | – | The server selects the highest format that
is supported by the drive on which a volume is mounted. Attention: Avoid specifying DRIVE when a mixture of drives is
used within the same library. For example, do not use this option
for a library that contains some drives that support recording formats
superior to other drives.
|
ULTRIUM | 100 GB | Uncompressed format, using Ultrium cartridges |
ULTRIUMC | See note 200 GB |
Compressed format, using Ultrium cartridges |
ULTRIUM2 | 200 GB | Uncompressed (standard) format, using Ultrium 2 cartridges |
ULTRIUM2C | See note 400 GB |
Compressed format, using Ultrium 2 cartridges |
ULTRIUM3 | 400 GB | Uncompressed (standard) format, using Ultrium 3 cartridges |
ULTRIUM3C | See note 800 GB |
Compressed format, using Ultrium 3 cartridges |
ULTRIUM4 | 800 GB | Uncompressed (standard) format, using Ultrium 4 cartridges |
ULTRIUM4C | See note 1.6 TB |
Compressed format, using Ultrium 4 cartridges |
ULTRIUM5 | 1.5 TB | Uncompressed (standard) format, using Ultrium 5 cartridges |
ULTRIUM5C | See note 3.0 TB |
Compressed format, using Ultrium 5 cartridges |
ULTRIUM6 | 2.5 TB | Uncompressed (standard) format, using Ultrium 6 cartridges |
ULTRIUM6C | See note 6.25 TB |
Compressed format, using Ultrium 6 cartridges |
Note: If this format uses the tape drive hardware compression
feature, depending on the effectiveness of compression, the actual
capacity might be greater than the listed value.
|
You must specify this value as an integer followed by K (kilobytes), M (megabytes), G (gigabytes), or T (terabytes). For example, ESTCAPACITY=100G specifies that the estimated capacity for a volume in this device class is 100 GB.
The smallest value that is allowed is 1 MB (that is, ESTCAPACITY=1M). To force the IBM Tivoli Storage Manager server to determine the estimated capacity for the volumes that are assigned to this device class, specify ESTCAPACITY="".
For more information about estimated capacities, see Table 2.
If you previously established a media label naming convention that supports your current management system, use a volume prefix that conforms to your naming conventions.
This parameter can improve response time for sequential access media mounts by leaving previously mounted volumes online. However, for EXTERNAL library types (that is, for a library that is managed by an external media management program), you can enhance device sharing between applications by setting this parameter to a low value (for example, two minutes).
If you plan to use the simultaneous-write function, ensure that sufficient drives are available for the write operation. If the number of drives needed for a simultaneous-write operation is greater than the value of the MOUNTLIMIT parameter for a device class, the transaction fails.
update devclass ltotape mountlimit=2