WORM drives anyone ?

[Root Boy Jim]

	   Since you can buy a SCSI drive for $4000 and a SCSI controller for
   $1500 or less, I assume a major bottleneck is the non-trivial software
   interface, i.e. how to make a write-once device useful. Does anyone have
   any thoughts as to the "proper" approach to allow "transparent" filesystem-
   like access, especially under UNIX ? It seems to me that a fileserver
   daemon could be written to emulate a UNIX filesystem and hide the inherent
   issues of the WORM...

There are several approaches to WORMS. The most obvious is tape emulation,
and some WORM drives actually plug into tape controllers and emulate them.
Disk emulation is harder. You can either keep the index on a real disk, or
write it out to create a permanent frozen read-only file system. This
usually requires a specialized driver, as well as utilities to squeeze
good data from one drive onto another.

Yet another approach is taken by Epoch Systems in Marlborough, Mass. They
gave us a presentation and told us not to say anything, so I won't say
anything else except to give their phone number, which is (617) 481-3717,
and to say that I was relatively impressed. They should announce soon,
and will probably visit your site and give their pitch if you're interested.

				   Cheers,
				   Dan Ts'o		212-570-7671
				   Dept. Neurobiology	dan at rna.rockefeller.edu
				   Rockefeller Univ.	...cmcl2!rna!dan
				   1230 York Ave.		rna!dan at nyu.edu
				   NY, NY 10021		tso at rockefeller.edu

	(Root Boy) Jim Cottrell	<rbj at icst-cmr.arpa>
	National Bureau of Standards
	Flamer's Hotline: (301) 975-5688
	The opinions expressed are solely my own
	and do not reflect NBS policy or agreement
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