[Coco] luns and scsi disks

Tim Fadden t.fadden at cox.net
Sat Feb 18 10:41:28 EST 2017

Below is the listing for super driver disk descriptor.

Why do you even have lun number even on there?  it has no relevance. A 
lun can be  an entire disk, a partition, or several disks raided in any 
fashion. It is a logical name given to a host so they don't have to know 
what lies beneath at the hardware level.  In the case of coco's the lun 
and scsi ID is basically the exact same thing.  If you partition the 
disk, I guess you could define each partition as a lun.  the "nam" you 
give the disk/partition is really what the definition of a lun is.  In 
practice, luns are used in large san's where several hosts are 
connecting to their storage over the san, and the large data farm of 
storage is split up into "luns" to present to the host.


(offset $16) for SCSI Low Level Driver


SCSI Logical Unit Number of drive (0-7) (ignored if bit 3 is 1)

Turbo Mode: 1 = use accelerated handshaking, 0 = standard

HDB-DOS Partition Flag

SCSI ID of the drive or controller (0-7)

Tim Fadden
"Hey Schmidt, don't forget about the six P's.
Proper Preparation Prevents Piss-Poor Performance!"

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