RE: iSCSI: Re: iSCSI & Linked Commands

["Douglas Otis" <dotis@sanlight.net>]

Robert,

Relative addressing is not defined because that is the only means of
addressing.  Relative to the last block.

Doug


> Doug,
>
> Relative addressing is not defined in the SSC command set nor
> in the SPC command set for tapes.
>
> Bob
>
> >  -----Original Message-----
> >  From: Douglas Otis [mailto:dotis@sanlight.net]
> >  Sent: Monday, April 23, 2001 9:36 AM
> >  To: Stephen Bailey; ips@ece.cmu.edu
> >  Subject: RE: iSCSI: Re: iSCSI & Linked Commands
> >
> >
> >  Stephen,
> >
> >  Unlike random access devices, sequential access devices operate with
> >  relative addressing.  For random access devices, this is a
> >  seldom used
> >  option.  There is a requirement to bind commands together to
> >  ensure order of
> >  execution on these devices.  By popular, you mean not sequential?
> >
> >  Doug
> >
> >
> >  > Julian,
> >  >
> >  > > According to your logic no FCP implementation can use
> >  linked commands?
> >  > > Is this true for all OS's?  Is it a verified fact or foloklor?
> >  >
> >  > In my experience it's fact.  I have never used a SCSI
> >  stack which both
> >  > supported AND used linked commands.  Like some others
> >  here, I always
> >  > assumed AIX might :^) Ralph has pointed out that T10 is well aware
> >  > that the feature is not popular.  There are other ways of
> >  > accomplishing the same thing that are less likely to blow
> >  up in your
> >  > face.
> >  >
> >  > > Is it so also for the new MS StorPort driver?
> >  >
> >  > I don't know, but I'd be really surprised if they did use linked
> >  > commands.  You have to be pretty nuts to rely on a feature
> >  that's not
> >  > even exercised by most SCSI implementations.
> >  >
> >  > Steph
> >  >
> >
> >
>