> -----Original Message-----
> From: Steve Dirickson [mailto:[log in to unmask]]
>
> > [...] I am trying to find out how many disks I
> > can hang off
> > of one FW/SCSI. I am interested in throwing all the rules
> > about performance
> > and stability and the dip switches on the hardware out the
> door. I am
> > interested in just the path limitations. Currently 987 is not
> > being used at
> > night. [...]
>
> A 16-bit SCSI channel (a.k.a. "Wide" SCSI) supports 16
> targets, one of which
> is the adapter. Each of the other 15 targets can be drives,
> scanners, [etc...]
> Each target may
> contain up to 8 Logical Unit Numbers (LUNs). [...] If none of
> the target
> devices on the bus use LUNs, the maximum number of devices on
> the bus (other
> than the adapter) is 15. If all targets use LUNs, 120 devices can be
> addressed. I've never seen a stand-alone disk drive that uses
> LUNs, though
> they may exist.

Another possibility still would be stand-alone hardware RAID(-5) units.  One
in particular that comes to mind is from a company called "Medea", and they
offer a 100-GB drive unit that internally consists of 5 20GB drives.  (These
are primarily aimed at people doing video editing, BTW).  From the SCSI
point of view, it "looks" like a 100gb drive taking up a single ID/LUN, but
internally it really is multiple devices -- another side effect is that the
"burst" speed can be "sustained" far longer than ordinary drives...

>
> Steve Dirickson   WestWin Consulting
> [log in to unmask]   (360) 598-6111
>