Device Class:
A device class defines the type of storage hardware or Media used for a particular storage pool.
The two main categories of devices supported for storage pools are-:
Random access devices
Sequential access devices
Random access devices-: It refers to devices that can be accessed in a random fashion, that is, data can be read from or written to any part of the media in a series of I/Os. Random access devices are usually magnetic disks.
Sequential access devices-:It refers to devices where data is accessed sequentially, that is, one block at a time, one after the other. Sequential access devices usually are tape devices and/or optical devices such as MO,CD, or DVD. It is also possible to configure a sequential access storage pool on a disk device (using a FILE device class).
click here to see the Tivoli Storage Manager Supported Devices..
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