Device class represents set of storage devices.
TSM Server supports multiple device classes. They are:
1) DISK DEVICE CLASS:
By using Disk Device Class we can create N no. of Disk storage pools. Disk storage pools are also called as Random access storage pool. Because we can perform multiple operations on disk storage pools. By default at the time of installation itself we get Disk device class. We have to create disk storage pools and once storage pools are created we have to define volumes under this storage pools.
2) FILE DEVICE CLASS:
By using file device class we can use disk as sequential access device. Once we define file device class in TSM Server from then the disk acts as sequential access device. But we have to def max scratch allowed and also we have define maximum capacity of each volume which is created by using file device class. Command to define file device class is:
Def devc deviceclassname dev directory=location
3) LTO CLASS:
Before defining LTO class we have to define Tape Library. Under LTO class have to define library storage pool which consists of tapes. We should also define mount limit and mount retention and max scratch allowed in LTO class. Commands to define LTO class.
Command to define a library:
Def library libraryname libray
Command to define LTO class:
Def devc deviceclassname dev mountlimit=number mountretention=minutes
a) MOUNT LIMIT:
Here mount limit parameter specifies how many no. of tape mounts the device class should allow at a time.
b) MOUNT RETENTION:
This parameter specifies how many no. of minutes the tape can be in ideal state in the tape drive once the read/ write operation was done on the mounted tape.
If we specify mount retention=60 then the tape will be in ideal state in the tape drive for 60 minutes and after 60 minutes the tape will automatically dismounted from the tape drive.
If any tape request comes in between or within 60 minutes when the tape is in ideal state then the tape will get dismounted automatically and new tape will get mounted.
TSM Server supports multiple device classes. They are:
1) DISK DEVICE CLASS:
By using Disk Device Class we can create N no. of Disk storage pools. Disk storage pools are also called as Random access storage pool. Because we can perform multiple operations on disk storage pools. By default at the time of installation itself we get Disk device class. We have to create disk storage pools and once storage pools are created we have to define volumes under this storage pools.
2) FILE DEVICE CLASS:
By using file device class we can use disk as sequential access device. Once we define file device class in TSM Server from then the disk acts as sequential access device. But we have to def max scratch allowed and also we have define maximum capacity of each volume which is created by using file device class. Command to define file device class is:
Def devc deviceclassname dev directory=location
3) LTO CLASS:
Before defining LTO class we have to define Tape Library. Under LTO class have to define library storage pool which consists of tapes. We should also define mount limit and mount retention and max scratch allowed in LTO class. Commands to define LTO class.
Command to define a library:
Def library libraryname libray
Command to define LTO class:
Def devc deviceclassname dev mountlimit=number mountretention=minutes
a) MOUNT LIMIT:
Here mount limit parameter specifies how many no. of tape mounts the device class should allow at a time.
b) MOUNT RETENTION:
This parameter specifies how many no. of minutes the tape can be in ideal state in the tape drive once the read/ write operation was done on the mounted tape.
If we specify mount retention=60 then the tape will be in ideal state in the tape drive for 60 minutes and after 60 minutes the tape will automatically dismounted from the tape drive.
If any tape request comes in between or within 60 minutes when the tape is in ideal state then the tape will get dismounted automatically and new tape will get mounted.