Subject: RE: iscsi : iscsi parameter default values

From: "Julian Satran" <[email-masked]>
Date: Fri, 28 Sep 2001 18:17:34 +0300

Eddy,

The text (cleaned) says:

   For numerical negotiations, the responding party MUST respond with the
   required key.

   Binary negotiations (for keys taking the values yes or no) are a
   restricted form of numerical negotiations and the result is a key
   dependent Boolean function of the two inputs. The negotiation MUST
   proceed ONLY up to the point where both parties can unequivocally
   compute the result based on new values; continuing beyond this point is
   OPTIONAL.

   Comments?
   Julo

                    "Eddy                                                                         
                    Quicksall"            To:     John Hufferd/San Jose/IBM@IBMUS, Julian         
                    <EQuicksall@med        Satran/Haifa/IBM@IBMIL                                 
                    iaone.net>            cc:     <[email-masked]>                               
                                          Subject:     RE: iscsi : iscsi parameter default values 
                    28-09-01 16:44                                                                
                    Please respond                                                                
                    to "Eddy                                                                      
                    Quicksall"                                                                    

I don't have any problem anymore with the ImmediateData default because the
spec has been changed to say:

 For numerical (and binary) negotiations, the responding party MUST
 respond with the required key.

But, there is still the issue I have pointed out below, that is ...

Section 5 says:

 The initial Login request MUST include the InitiatorName and
 SessionType key=value pairs.

Since SessionType is REQUIRED, naming a default would imply a possible
typo in the spec (i.e., either the SessionType is not required or the
default has no meaning).

I suggest that we take the Default out of SessionType or change section 5
to
say:

 The initial Login request MUST include the InitiatorName key=value pair.
 If the SessionType is not specified, the default type will be Normal.

Eddy

-----Original Message-----
From: John Hufferd [mailto:[email-masked]]
Sent: Friday, September 28, 2001 4:33 AM
To: Julian Satran
Cc: [email-masked]
Subject: RE: iscsi : iscsi parameter default values

I also agree with this.  It should be yes.

.
.
.
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: [email-masked]

Julian Satran/Haifa/IBM@[email-masked] on 09/27/2001 09:50:21 AM

Sent by:  [email-masked]

To:   [email-masked]
cc:
Subject:  RE: iscsi : iscsi parameter default values

The one that I have trouble living with is ImmediateData. This is
important
for low-end desktops and hardly matters for large boxes.
As such I would suggest it stays as yes.

Julo

                    "Eddy
                    Quicksall"            To:     "'Santosh Rao'"
<[email-masked]>,
                    <EQuicksall@med        <[email-masked]>
                    iaone.net>            cc:
                    Sent by:              Subject:     RE: iscsi : iscsi
parameter default values
                    [email-masked]
                    mu.edu

                    27-09-01 17:22
                    Please respond
                    to "Eddy
                    Quicksall"

I like your defaults below.

But, section 5 says:

 The initial Login request MUST include the InitiatorName and
 SessionType key=value pairs.

Since SessionType is REQUIRED, naming a default would imply a possible
typo
in the spec.

Eddy

-----Original Message-----
From: Santosh Rao [mailto:[email-masked]]
Sent: Wednesday, September 26, 2001 10:29 PM
To: [email-masked]
Subject: iscsi : iscsi parameter default values

All,

With the issue of mode page vs. login keys having [almost] drawn to a
close, I would like to
raise the below issues again, on the subject of default values for login
keys and other iscsi
parameters :

   * In keeping with traditional use of scsi mode pages, iscsi should
not specify any default
     settings for any mode pages that continue to exist for iscsi.
"Default values" for mode
     pages are target specific and should not be bound to the protocol
draft.

   * MORE IMPORTANTLY, I read the default for EMDP as being set to 1
:-<  This implies that
     targets must be always prepared to deal with out of order data and
initiators must be
     prepared to deal with out of order data, unless the initiator
performs a mode select to
     disable it. [which defeats all the previous advantages gained thru
mandating use of login
     keys for other negotiations.]. A default, if it were to exist,
should be 0. (in-order, by
     default).

   * Conservative specification of defaults for login keys along the
following lines :
                            MaxConnections = 1
                            FMarker = "no"
                            InitialR2T = "yes"
                            BidiInitialR2T = "yes"
                            ImmediateData = "no"
                            DataPDULength = 16
                            MaxOutstandingR2T = 1
                            DataPDUInOrder = "yes"
                            ErrorRecoveryLevel = 0
                            SessionType = "normal"

   * Should the iscsi protocol require a "Lun Control Mode Page"? IOW,
is an EnableCRN bit
     required at the transport layer ? If the device server capability
is to be negotiated , I
     suggest this bit be moved to a SCSI ULP Mode Page such as the
"Control Mode Page", through a
     T10 change as a part of the SCSI changes being driven by iscsi.

Comments ?

Thanks,
Santosh

Santosh Rao wrote:

> There are the separate issues of :
>
>    * iscsi's specification of defaults for its mode pages which is not
in line with mode page
>      usage. This impacts the target's ability to enforce values other
than the protocol
>      specified default, if the initiator were to not use mode
sense/select.
>
>    * default settings for login keys.
>
>    * Is there a need for the "LUN Control Mode Page" and whether
"Enable CRN" should be in a
>      transport specific mode page ?
>
> which need to be driven to closure as well.
>
> Regards,
> Santosh

---

From: Paul Koning <[email-masked]>
Date: Fri, 28 Sep 2001 13:02:38 -0400

>    compute the result based on new values; continuing beyond this point is

The last sentence contradicts itself.  If you "MUST proceed ONLY..."
then by definition you cannot proceed further, so saying that
proceeding further is optional makes no sense.  Even ignoring that,
I still have no idea what the last sentence means.

Also, "yes" and "no" aren't numbers, so perhaps you should say "for
keys taking the values 1 (meaning "yes") and 0 (meaning "no")..."

      paul