What is the difference between volume and logical unit number (LUN)?
A volume normally refers to a "disk" created via a "volume manager" such as Veritas or a volume created by an operating system such as Windows NT. A LUN refers to a "logical unit number" presented to a host as a SCSI ID. (i.e., LUN number 1 specifies SCSI ID 1 on that port. Therefore, the term volume can be considered software based and LUN considered hardware based.
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