Subject: Re: SCSI network
To: None <>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: tech-kern
Date: 10/16/1999 10:04:56
> Not what I would call polling.  You issue a read, the target
> disconnects until it has something to send.  Whenever a read is
> complete a new read is issued.

For the asymmetric solution this is the way I'd go.

> So, there is always a read in progress, but you do not have to
> continuously issue reads when there is no data and when there is data
> you get interrupted (by the select) so you don't have to wait for a
> polling interval to expire.

select??  This is the kernel we're talking about here; userland would
just see it as another network interface.

> As I said, this is not the preferred solution.

Quite.  As you say, once you have the SCSI subsystem ready to be a
target, you might as well have both hosts ready to be targets, unless
one of them has a spare SCSI bus dedicated to the purpose (= one it
never has to be initiator on), which while it may have applications
does not describe the setup that prompted me to consider the project.

> Still, there may be SCSI adaptors which have a complete initiator
> implementation, including reselection (after disconnect) but simply
> don't support target mode.

Does anyone know of any such SCSI adapter?  In particular, does anyone
know of any such SCSI adapter for any hardware NetBSD runs on or is
likely to run on?

					der Mouse

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