Can same physical storage (user data) be accessed through two different LBAs ?

Nadesan Narenthiran Nadesan.Narenthiran at
Thu Apr 23 18:48:47 PDT 2015

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Does SCSI explicitly prohibit accessing the same physical storage location
through two different handles / LBAs (on drives - single LUN devices) ?
The issue is really to do with access to the same user data rather than the
actual storage location.  The question was over security whether if
restricting access to a LBA in turn restricts access to that user data.
This is an off-shoot from a conversation in another reflector.	In that other
conversation I got educated that SCSI does not prohibit access to the same
physical location through two different LUNs and that implementations exist
that use this flexibility.  So I want the answer restricted within a single
Also ignore other cases such as copy managers, replication, etc, etc, etc
existing within this device that can copy the data over.
I believe it does because the SBC model clause explains that user data is in
a Logical Block and that a unique LBA maps to the Logical Block.  But there
are no shalls in this explanation.  And I want to be sure all the
explanations about physical blocks and as such do not override this.
If it does prohibit such access, please point out the place(s) that prohibit
this access.
Have a nice day.

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