Re: iSCSI: Question about ErrorRecoveryLevel

["Mallikarjun C." <cbm@rose.hp.com>]

Comments in text.
--
Mallikarjun

Mallikarjun Chadalapaka
Networked Storage Architecture
Network Storage Solutions
Hewlett-Packard MS 5668 
Roseville CA 95747
cbm@rose.hp.com

 
> > The reason MUST language was not used is because the text in question is
> > defining the terminology, but is not phrased in such a way as to place requirements
> > on implementations.  It is similar to several terminology descriptions in chapter 2.
> >
> > My intent when I wrote that text was - because the negotiation of the
> > ErrorRecoveryLevel follows the regular negotiation rules (i.e. don't originate
> > a proposal that you cannot support, and the result function is "minimum"), no
> > additional MUST/SHOULD/MAY language is necessary.  But if you recommend
> > explicit text, I suggest we add the following at the end of the last para of
> > text in 5.13 -
> 
> That though doesn't answer my question. :-) The main question is does
> ErrorRecoveryLevel 1 imply both within-command and within-connection
> support, or does it imply at least one and maybe both?

Both.  It is clear to me by the way the terminology is defined ( note the "and"
in 5.13).  I thought your question had to do with implementation expectations.

> > When a defined value of ErrorRecoveryLevel is proposed by an
> > originator in a text negotiation, the originator MUST support the
> > functionality defined for the ErrorRecoveryLevel or functionality
>                                                    ^^
> Is this supposed to be "and"?

Okay, "and" may be clearer (the "or" was used because only one of
the levels can be picked by the reponder).

> 
> > corresponding to any defined value numerically less than the proposed.
> > When a defined value of ErrorRecoveryLevel is returned by a responder
> > in a text negotiation, the responder MUST support the functionality
> > corresponding to the ErrorRecoveryLevel it is accepting.
> 
> If "and" is appropriate, then shouldn't we add, "and all numerically lower
> levels" to the end of the paragraph?

I don't see the need.  If I'm accepting X, then I am promising to employ 
X in the session operation.  OTOH, if I'm offering X, it means that I'm
promising to settle for any Y, where 0<=Y<=X, that the other side would
return in the response.

IMO, the point that the functionality is hierarchical doesn't need to be made 
everywhere.