Compaq External RAID Controller & Subsystem Infortrend Operation Manual page 45

NOTE:
5.
6.
The controller is totally independent from host operating system.
Host operating system will not be able to tell whether the attached
storage is a physical hard drive or the virtual system drives created
by the RAID controller.
2-6
A "Logical Drive" is a set of drives grouped together to operate under a
given RAID level and it appears as a single contiguous volume. The
controller is capable of grouping drives into as many as 128 logical
drives, configured in the same or different RAID levels.
A total of 32 "Logical Volumes" can be created each from one or several
logical drives. A logical drive or logical volume can be divided into a
maximum of 64 "Partitions."
The next step is to make logical drives or storage partitions
available through the host ports. When associated with a host
ID or LUN number, each capacity volume appears as one
system drive. The host SCSI or Fibre adapter will recognize the
system drives after the host bus is re-initialized.
The last step is to save your configuration profile in the host
system drive or to the logical drives you created.
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