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Please clarify what do we mean by LUN and Array ? and if they are similar in meaning?.

The confusion is because both are presented to specific servers by the combination of different Hard disks or individual Hard disk ( correct me if am worng )

EEAA
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Guruprasad
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1 Answers1

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A LUN (Logical Unit Number) is a number used to uniquely identify any device that is attached to a SCSI device chain, or anything that emulates a SCSI device chain.

Some devices that could be attached to a device chain and would be assigned a LUN include:

  • A single hard disk.
  • An array of hard disks.
  • A tape drive.
  • A CD-ROM drive.

It's important to remember that while SCSI is mostly deprecated today, many operating systems and devices emulate SCSI-like bahavior. This includes SAN technologies like iSCSI and Fiber Channel, which you may be referring to here.

Kyle Smith
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    Great answer Kyle but if you don't mind I'd like to state in Fisher Price terms that in general a LUN is a bit of disk space on an array that's presented to one or more clients. – Chopper3 Jul 06 '11 at 14:00
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    SCSI is *not* deprecated. SCSI is a command set that is still very alive. Yes, the old *parallel* SCSI interconnect is on death's door, but SAS, FC, iSCSI, etc. are all technologies that use the SCSI command set that aren't going away any time soon. – EEAA Jul 06 '11 at 15:19
  • @ErikA - +1 Good point. – Kyle Smith Jul 06 '11 at 17:33