RE: iSCSI: Re: iSCSI & Linked Commands

[Robert Snively <rsnively@Brocade.COM>]

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
>  >
>  
>