To run properly, the dump command needs to know the maximum capacity of the destination tape drive. It determines this capacity in one of two ways, depending on the tape device name that you use:
The physical device name – you must include the capacity parameter in the dump command. This parameter specifies the maximum number of bytes to write to a tape device.
Check your tape’s capacity, and keep the following in mind:
The minimum value that the capacity parameter can accept is 5 databases pages, 2K each.
The maximum value that the capacity parameter can accept is 4,294,967,295K.
The actual capacity value should be 70 to 80 percent of the true capacity of the tape.
If you omit the capacity parameter for NT, Backup Server writes the maximum number of bytes for the specified tape device.
The logical device name – the command uses the size parameter stored in the sysdevices system table.
You can override that value by using the capacity parameter as described in the preceding list item.