Return-Path: X-Sieve: cmu-sieve 2.0 Return-Path: Received: (from majordom@localhost) by ece.cmu.edu (8.11.0/8.10.2) id h0NJ1wJ13253 for ips-outgoing; Thu, 23 Jan 2003 14:01:58 -0500 (EST) X-Authentication-Warning: ece.cmu.edu: majordom set sender to owner-ips@ece.cmu.edu using -f Received: from mail1irv.inside.istor.com (host28.istor.com [66.134.214.28]) by ece.cmu.edu (8.11.0/8.10.2) with ESMTP id h0NJ1uW13244 for ; Thu, 23 Jan 2003 14:01:56 -0500 (EST) X-MimeOLE: Produced By Microsoft Exchange V6.0.5762.3 content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----_=_NextPart_001_01C2C311.CC1BE8D5" Subject: RE: iSCSI: LUN in a ping Date: Thu, 23 Jan 2003 11:01:12 -0800 Message-ID: <7D036BD3216A084DB1BD9D62BCEAF290166784@mail1irv.inside.istor.com> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: iSCSI: LUN in a ping Thread-Index: AcLDEMsFsqO+L51DTW2ik+NJkmE07wAAI1/g From: "Ken Craig" To: "Julian Satran" Cc: Sender: owner-ips@ece.cmu.edu Precedence: bulk This is a multi-part message in MIME format. ------_=_NextPart_001_01C2C311.CC1BE8D5 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Hello Julo, =20 For those of us that weren't here 18 months ago can you refresh us on your explanation or point us to where it is since I too wonder why a SCSI Target would not use the mechanisms it already has in place to notify an initiator of a LUN inventory change? =20 Thanks, Ken Craig -----Original Message----- From: Julian Satran [mailto:Julian_Satran@il.ibm.com]=20 Sent: Thursday, January 23, 2003 8:47 AM To: Eddy Quicksall Cc: ips@ece.cmu.edu; Julian Satran; owner-ips@ece.cmu.edu; Rod Harrison Subject: RE: iSCSI: LUN in a ping =09 =09 Eddy,=20 =09 We all appreciate you opinion - but this has been hotly debated more than 18 months ago.=20 And I recall sending you an explanation regarding the middle boxes and how they handle the LUN for routing in a "clustered" target.=20 And your comment about a "requirement with no good reason" besides being derogatory does not add any value to the discussion.=20 =09 Julo=20 =09 =09 =09 Eddy Quicksall =20 Sent by: owner-ips@ece.cmu.edu=20 23/01/03 17:19=20 To Rod Harrison , Julian Satran , ips@ece.cmu.edu=20 cc Subject RE: iSCSI: LUN in a ping =09 For that, wouldn't the target generate REPORTED LUNS DATA HAS CHANGED (3F/0E)? =09 It is my opinion that this is just another requirement that has been put on the target for no good reason. =09 It should be up to the target as to if the LUN field has meaning and the initiator should be the one that has a requirement to echo the value. =09 Eddy =09 -----Original Message----- From: Rod Harrison [mailto:rod.harrison@windriver.com] Sent: Wednesday, January 22, 2003 1:52 PM To: Eddy Quicksall; Julian Satran; ips@ece.cmu.edu Subject: RE: iSCSI: LUN in a ping =09 =09 =09 The initiator might try to rediscover the LUN topology if it sees a NOP from a LUN that it previously thought was not present. =09 - Rod =09 -----Original Message----- From: owner-ips@ece.cmu.edu [mailto:owner-ips@ece.cmu.edu]On Behalf Of Eddy Quicksall Sent: Wednesday, January 22, 2003 10:28 AM To: Julian Satran; Eddy Quicksall; ips@ece.cmu.edu Subject: RE: iSCSI: LUN in a ping =09 =09 Yes, I remember that but the necessity for the target to set it should be up to the target because the initiator should not be trying to interpret it (it should only be required to echo it). =09 Is there a case where the initiator will interpret the LUN? =09 Eddy =09 -----Original Message----- From: Julian Satran [mailto:julian@cs.haifa.ac.il] Sent: Wednesday, January 22, 2003 12:43 AM To: 'Eddy Quicksall'; ips@ece.cmu.edu Subject: RE: iSCSI: LUN in a ping =09 =09 TTT & LUN uniquely identify the "origin" (if target is a "composite" each of the parts can issue their own TTTs - no coordination needed). =09 Regards, Julo =09 =09 -----Original Message----- From: owner-ips@ece.cmu.edu [mailto:owner-ips@ece.cmu.edu] On Behalf Of Eddy Quicksall Sent: 22 January, 2003 00:07 To: ips@ece.cmu.edu Subject: iSCSI: LUN in a ping =09 =09 Does anyone know why we added "the LUN must be valid" for a target initiated ping? It would seem that it is N/A when the ping is just being used to checkup on the connection. =09 What will the initiator do with the LUN anyway? =09 10.19.3 LUN A LUN MUST be set to a correct value when the Target Transfer Tag is valid (not the reserved value 0xffffffff). =09 Eddy mailto: Eddy_Quicksall@iVivity.com =09 =09 =09 ------_=_NextPart_001_01C2C311.CC1BE8D5 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Message
Hello=20 Julo,
 
For=20 those of us that weren't here 18 months ago can you = refresh
us on=20 your explanation or point us to where it is since I = too
wonder=20 why a SCSI Target would not use the mechanisms it
already has in place to notify an initiator = of a LUN=20 inventory
change?
 
Thanks,
Ken=20 Craig
-----Original Message-----
From: = Julian Satran=20 [mailto:Julian_Satran@il.ibm.com]
Sent: Thursday, January = 23, 2003=20 8:47 AM
To: Eddy Quicksall
Cc: ips@ece.cmu.edu; = Julian=20 Satran; owner-ips@ece.cmu.edu; Rod Harrison
Subject: RE: = iSCSI: LUN=20 in a ping


Eddy,=20

We all appreciate you opinion = - but this=20 has been hotly debated more than 18 months ago.
And I recall sending you an explanation = regarding the=20 middle boxes and how they handle the LUN for routing in a "clustered"=20 target.
And your comment = about a=20 "requirement with no good reason" besides being derogatory does not = add any=20 value to the discussion.

Julo


Eddy = Quicksall=20 <eddy_quicksall@ivivity.com>
Sent by: owner-ips@ece.cmu.edu=20

23/01/03 17:19

To
Rod = Harrison=20 <rod.harrison@windriver.com>, Julian Satran=20 <julian@cs.haifa.ac.il>, ips@ece.cmu.edu=20
cc
Subject
RE: iSCSI: = LUN in a=20 ping

=




For that, wouldn't the target generate REPORTED LUNS DATA = HAS=20 CHANGED
(3F/0E)?

It is my opinion that this is just another=20 requirement that has been put on
the target for no good = reason.

It=20 should be up to the target as to if the LUN field has meaning and=20 the
initiator should be the one that has a requirement to echo the=20 value.

Eddy

-----Original Message-----
From: Rod = Harrison=20 [mailto:rod.harrison@windriver.com]
Sent: Wednesday, January 22, = 2003 1:52=20 PM
To: Eddy Quicksall; Julian Satran; ips@ece.cmu.edu
Subject: = RE:=20 iSCSI: LUN in a ping



The initiator might try to = rediscover the=20 LUN topology if it sees a NOP from
a
LUN that it previously = thought was=20 not present.

- Rod

-----Original Message-----
From:=20 owner-ips@ece.cmu.edu [mailto:owner-ips@ece.cmu.edu]On Behalf = Of
Eddy=20 Quicksall
Sent: Wednesday, January 22, 2003 10:28 AM
To: Julian = Satran;=20 Eddy Quicksall; ips@ece.cmu.edu
Subject: RE: iSCSI: LUN in a=20 ping


Yes, I remember that but the necessity for the target = to set=20 it should be up
to the target because the initiator should not be = trying to=20 interpret it (it
should only be required to echo it).

Is = there a=20 case where the initiator will interpret the=20 LUN?

Eddy

-----Original Message-----
From: Julian = Satran=20 [mailto:julian@cs.haifa.ac.il]
Sent: Wednesday, January 22, 2003 = 12:43=20 AM
To: 'Eddy Quicksall'; ips@ece.cmu.edu
Subject: RE: iSCSI: LUN = in a=20 ping


TTT & LUN uniquely identify the "origin" (if = target is a=20 "composite"
each of the parts can issue their own TTTs - no = coordination=20 needed).

Regards,
Julo


-----Original=20 Message-----
From: owner-ips@ece.cmu.edu = [mailto:owner-ips@ece.cmu.edu] On=20 Behalf Of
Eddy Quicksall
Sent: 22 January, 2003 00:07
To:=20 ips@ece.cmu.edu
Subject: iSCSI: LUN in a ping


Does = anyone know=20 why we added "the LUN must be valid" for a target
initiated ping? = It would=20 seem that it is N/A when the ping is just being
used to checkup on = the=20 connection.

What will the initiator do with the LUN=20 anyway?

10.19.3 LUN
A LUN MUST be set to a correct value = when the=20 Target Transfer Tag is
valid (not the reserved value=20 0xffffffff).

Eddy
mailto:=20 = Eddy_Quicksall@iVivity.com


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