Re: is TargetName always mandatory or not?

["John Hufferd" <hufferd@us.ibm.com>]

Andre,
I looked again through the document and No where could I find a statement
that you claimed as "a nexus, and therefore an iSCSI session, is uniquely
identified by the InitiatorName, ISID, TSID, and portal group tag".  It is
the InitiatorName, ISID, TSID, with the TargetName and PortalGroup.

Please point out to me in the Spec (8 or above), where  I can find your
statement on I_T Nexus.

I did find the following (please ignore for this conversation the "i" and
't" stuff):

"- Session: The group of TCP connections that link an initiator with a
target, form a session (loosely equivalent to a SCSI I-T nexus). TCP
connections can be added and removed from a session. Across all connections
within a session, an initiator sees one "target image".  "

" - I_T nexus: According to [SAM2], the I_T nexus is a relationship between
a SCSI Initiator Port and a SCSI Target Port. For iSCSI, this relationship
is a session, defined as a relationship between an iSCSI Initiator's end of
the session (SCSI Initiator Port) and the iSCSI Target's Portal Group. The
I_T nexus can be identified by the conjunction of the SCSI port names; that
is, the I_T nexus identifier is the tuple (iSCSI Initiator Name + 'i'+
ISID, iSCSI Target Name + 't'+ Portal Group Tag). NOTE: The I_T nexus
identifier is not equal to the session identifier (SSID).  "

I have not found a place where Session ID is tied to the TSID.

Hence my comment that we also need to have the TargetName in the Initial
Login on all Connections.



.
.
.
John L. Hufferd
Senior Technical Staff Member (STSM)
IBM/SSG San Jose Ca
Main Office (408) 256-0403, Tie: 276-0403,  eFax: (408) 904-4688
Home Office (408) 997-6136
Internet address: hufferd@us.ibm.com


Andre Asselin/Raleigh/IBM@IBMUS@ece.cmu.edu on 10/31/2001 10:40:55 AM

Sent by:  owner-ips@ece.cmu.edu


To:   ips@ece.cmu.edu
cc:   John Hufferd/San Jose/IBM@IBMUS
Subject:  Re: is TargetName always mandatory or not?



John & Julian,
     How about this for the section 5 text:

The initial Login request of the first connection of a session (leading
login) MUST include the InitiatorName key=value pair. The initial login
request
of the leading Login MAY also include the SessionType key=value pair, in
which case if the SessionType is not "discovery", then the initial login
request
MUST also include the key=value pair TargetName.

John,
     I disagree with your second statement: I don't see any way you could
have 2 different sessions established within the same portal group with the
same InitiatorName, ISID, and TSID.  The spec. says that a nexus, and
therefore an iSCSI session, is uniquely identified by the InitiatorName,
ISID, TSID, and portal group tag.  There is no mention of TargetName
contributing to the identificaiton of a session.  In my opinion, a
non-leading connection should NOT have the TargetName, since it doesn't
contribute anything.

Andre Asselin
IBM ServeRAID Software Development
Research Triangle Park, NC




                    John
                    Hufferd/San          To:     Julian
Satran/Haifa/IBM@IBMIL
                    Jose/IBM@IBMUS       cc:     ips@ece.cmu.edu
                    Sent by:             Subject:     Re: is TargetName
always mandatory or not?
                    owner-ips@ece.
                    cmu.edu


                    10/31/2001
                    04:20 AM






Julian,
I think the TargetName should be included on the Initial Login Request on
the Leading Login.  It seem strange to permit the Authentication functions
to proceed if perhaps the intended Target is different then the one doing
the Authentication.  The way it currently is written, you could pass all
the Security test and then find out just before going into Full Function
Phase, that it was intended for some other Target.  Seems like a waste.

My I think that TargetName should also be on all connections on the Initial
Login Request.  Here is my thinking:

The SSID (ISID+TSID) is unique only with regards to a Specific Initiator
and Target Node Pair.  It is therefore not clear that just knowing the SSID
and InitiatorName is enough to understand what session the subsequent
connections are being attached to.  And it is possible that the CID could
be also overlapped with another session.

Therefore, I think it make since to determine all this on the initial Login
on every Connection, so you know at the beginning what values can be
negotiated, or that are being set to the right Session.

.
.
.
John L. Hufferd
Senior Technical Staff Member (STSM)
IBM/SSG San Jose Ca
Main Office (408) 256-0403, Tie: 276-0403,  eFax: (408) 904-4688
Home Office (408) 997-6136
Internet address: hufferd@us.ibm.com


Julian Satran/Haifa/IBM@IBMIL@ece.cmu.edu on 10/30/2001 11:33:50 PM

Sent by:  owner-ips@ece.cmu.edu


To:   ips@ece.cmu.edu
cc:
Subject:  Re: is TargetName always mandatory or not?



It is the leading login:

The section 5 paragraph will read:

The initial Login request of the first connection of a session (leading
login) MUST include the InitiatorName key=value pair. The leading Login
request MAY also include the SessionType key=value pair in which case if
the SessionType is not "discovery" then the leading Login Request MUST
also include the key=value pair TargetName.

Julo




Andre Asselin/Raleigh/IBM@IBMUS
Sent by: owner-ips@ece.cmu.edu
31-10-01 02:08
Please respond to Andre Asselin


        To:     "IPS Reflector (E-mail)" <ips@ece.cmu.edu>
        cc:
        Subject:        is TargetName always mandatory or not?



     In section 5 of the spec, it says "If the SessionType is not
"discovery" then the initial Login Request MUST also include the key=value
pair TargetName.".  However, in Appendix D, the description for TargetName
says it is Leading Only.
     Should TargetName not be Leading Only, or should the text in section
5
say that TargetName must be in the initial Login Request of a leading
connection?

Andre Asselin
IBM ServeRAID Software Development
Research Triangle Park, NC