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    iSCSI : New PDU opcode usage in rev 5.92



    Julian & All,
    
    I've got a quick question on how the new opcode layouts would work for
    dual mode scsi implementations. (i.e. initiators that responded in
    target mode or targets that acted as initiators also).
    
    The new opcode layout is :
    
    ----------------
    X|I| | | | | | |
    ----------------
    7 6 5 4 3 2 1 0
    
    where bits 5-0 -> opcode
    X -> retry bit
    I -> immediate bit
    
    The same values are used for the command as well as response opcodes and
    bits X & I are intended to both be set to 1 by targets.
    
    i.e. opcode for scsi command = scsi response = 0x01. the distinction b/n
    command and response is based on targets setting X & I bits to 1.
    
    Now, if an initiator [capable of target mode] sent the following
    commands, how would they be interpreted :
    
    1) 0xc4.
    is this a text command being retried in immediate mode, 
    or is it a text response ?
    
    2) 0xc1
    is this a scsi command being retried in immediate mode,
    or is it a scsi response ?
    
    3) 0xc2
    is this a scsi task mgmt command being retried in immediate mode,
    or is it a scsi task mgmt response ?
    
    etc.....
    
    - Santosh
    
    -- 
    #################################
    Santosh Rao
    Software Design Engineer,
    HP, Cupertino.
    email : santoshr@cup.hp.com
    Phone : 408-447-3751
    #################################
    


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Last updated: Tue Sep 04 01:05:00 2001
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