SORT BY:

LIST ORDER
THREAD
AUTHOR
SUBJECT


SEARCH

IPS HOME


    [Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

    RE: iSCSI: draft 7: Abort Task and RefCmdSN



    Sorry David - Since 06 this is not true anymore as they carry their own
    CmdSN for the purpose you mentioned (even when immediate) - but although
    this is good for clear task set it is not good enough for singles for which
    we still need both.
    
    Julo
    
    Black_David@emc.com@ece.cmu.edu on 06-08-2001 10:14:43
    
    Please respond to Black_David@emc.com
    
    Sent by:  owner-ips@ece.cmu.edu
    
    
    To:   Robert.Elliott@compaq.com, ips@ece.cmu.edu
    cc:
    Subject:  RE: iSCSI: draft 7: Abort Task and RefCmdSN
    
    
    
    ABORT TASK SET and CLEAR TASK SET also need the RefCmdSN to
    indicate where in the stream of commands they were issued.
    Julian - you probably need to revise your revised text to
    take this into account.
    
    --David
    
    > -----Original Message-----
    > From: Elliott, Robert [mailto:Robert.Elliott@compaq.com]
    > Sent: Sunday, August 05, 2001 1:36 PM
    > To: 'ips@ece.cmu.edu'
    > Subject: iSCSI: draft 7: Abort Task and RefCmdSN
    >
    >
    > The Task Management [function] Command PDU includes two fields
    > currently only used by the ABORT TASK function:
    >
    > 2.5.2 Referenced Task Tag
    >   Initiator Task Tag of the task to be aborted - for abort task
    >
    > 2.5.3 RefCmdSN [Referenced command sequence number]
    >   For abort-task the task CmdSN to enable task removal. If
    > RefCmdSN is
    >   is lower that ExpCmdSN or higher than MaxCmdSN the target
    > will ignore
    >   RefCmdSN.
    >
    > Both fields identify the task to be aborted.  The Referenced Task
    > Tag field sits at the SCSI level and matches the SAM-2 function
    > call description (SAM-2 revision 18):
    > 6.2 ABORT TASK
    >   Function call:
    >     Service Response = ABORT TASK (IN (I_T_L_Q Nexus) )
    >
    > The RefCmdSN field sits at the iSCSI level.
    >
    > I suggest removing one of these fields.  Having two ways to
    > specify the same thing just raises the question of what to do
    > when the values don't agree.  If that happens, should the
    > target:
    > send back a Reject PDU
    > abort both tasks
    > abort the task indicated by the Referenced Task Tag
    > abort the task indicated by the RefCmdSN
    > abort one of the tasks but also report an error
    > do any of the above
    >
    > Since task management functions in general may rely on the
    > SCSI tag (although Abort Task is the only current user of it),
    > I suggest keeping that flag and dropping the iSCSI field.
    >
    > --
    > Robert.Elliott@compaq.com
    > Compaq Computer Server Storage
    >
    
    
    
    


Home

Last updated: Tue Sep 04 01:04:05 2001
6315 messages in chronological order