Several months ago I sent a message to this list inquiring about SCSI
disks that supported a write protect jumper, and I promised to
summarize the responses. I then got very busy with a client, and am
just now coming up for air. So, belatedly, the summary follows.
Thanks again to all the wonderful people who responded to my query.
There seems to be quite a few options. There aren't too many low
capacity (less than 300 MB) drives though. Howard Chu gets the award
for the most complete and creative response!
Now I'm also wondering if there are any IDE drives that support a
write protect jumper...
From: Casper Dik <casper @
Well, the one GB I have is a FUJITSU-M2694ES (has write protect)
I did find the 2622/2623/2624 manual (290-550MB).
Those disks have write protect (CNH7, jumper 7-8)
Also the M2652 (2GB) also has write protect.
From: jpf @
com (Jack Flory)
Some Fujitsu disks (m2624) and dec (rz26m-e) have jumpers. Great
for adding a remote switch.
From: "Dan Thorson" <Dan_Thorson @
All of the Seagate Twin-cities designed drives support hardware write
protect. That is, the Barracuda (3.5"), Elite (5.25"), and Sabre (8")
From: randy @
com (Randy Davis)
Well, from experience, I know that the Maxtor XT-4380S does (about 300 MB
From: Jack Stewart <jack @
I know that the Micropolis 4110 will support it as well.
From: howard @
com (Howard Chu)
I saw your query on the firewalls list, I've been looking into this already.
The easiest solutions have all been removable media drives: Syquest cartridges,
magneto-optical, and floppy disk. In each case, the removable media has a
write-protect switch on the cartridge, making it relatively easy to change over
for updating purposes. Aside from that, they offer pretty widely varying
Hm, I guess I should add Bernoulli cartridges to the list, never used them
Media Capacity/Size Speed Drive cost Media cost
Floptical 21MB, 3-1/2" slow $250 $20
Syquest 88MB, 5-1/4" 20ms $250 $100
Syquest 105MB, 3-1/2" 14.5ms $220 $65
MO, Fujitsu 128MB, 3-1/2" 30ms $730 $40
Bernoulli 150MB, 5-1/4" 18ms $250 $100
MO, HP 650MB, 5-1/4" 27ms $2000 $100
MO, Maxoptix 1.0GB, 5-1/4" 24ms $2200-$2400 $190
MO, Maxoptix 1.3GB, 5-1/4" 19ms $3000-$3500 $190
The prices aren't current, they're from a February listing. They're probably
all around 5-10% cheaper by now.
Which drive you choose will depend on how much you want to pay, and how much
you want to store. If you're just storing a tripwire database, a 1.44 MB
floppy drive would do fine, and speed wouldn't be a big issue. If you want a
minimal read-only root partition, you only need from 16-32 MB, which any of
these drives could handle, but I would only consider the Syquest or Bernoulli
drives for performance reasons. For root and usr, you might be able to squeeze
a minimal OS distribution onto a Syquest or Bernoulli, or you might be forced
onto the larger magneto-optical media. My personal feeling is that MO drives
are too expensive for this purpose, but I haven't gone thru the numbers to find
the actual break-even point. (The MO drive prices vary because the cache size
varies from 1 to 4MB.)
Internet: don_jackson @
Phone: (408) 395-3516
Fax: (408) 395-3275