Re: iSCSI : LUN field in NOP-OUT & NOP-IN PDUs.

[Santosh Rao <santoshr@cup.hp.com>]

julian_satran@il.ibm.com wrote:
> 
> Santosh,
> 
> In NOPs the LUNs are used only if the exchange is originated by the target
> and then the LUN is
> has to be valid.
> 
> Otherwise the LUN is 0 (when the target task tag is ffffffff).

Julian,

If the target originates a NOP-IN, are you saying that the LUN field
must be valid and contain a non-zero LUN value ? FYI, LUN 0 is a valid
LUN. Why cannot the target use LUN 0 in this case ?

Also, what if the target is assigning target transfer tags on a per
session basis. What should such a target initialize the LUN field to ? 

IMO, the NOP-OUT and NOP-IN PDUs should allow a LUN field and let it be
set to LUN 0 if the targets are assigning tags on a per session basis.
(LUN 0 implying target SDP).

- Santosh




> As has been discussed in the past, the NOP-OUT and NOP-IN PDUs are
> transport specific and are used without any LUN context. Hence, it is
> not clear why a LUN field is required in either the NOP-OUT or NOP-IN
> PDUs.
> 
> Some side notes on this subject :
> 
> b) The NOP-IN PDU description shows a value of LUN 0 as reserved in the
> NOP-IN PDU diagram. Is not LUN 0 a valid LU number for a LU (?)
begin:vcard 
n:Rao;Santosh 
tel;work:408-447-3751
x-mozilla-html:FALSE
org:Hewlett Packard, Cupertino.;SISL
adr:;;19420, Homestead Road, M\S 43LN,	;Cupertino.;CA.;95014.;USA.
version:2.1
email;internet:santoshr@cup.hp.com
title:Software Design Engineer
x-mozilla-cpt:;21088
fn:Santosh Rao
end:vcard