Re: EIDE more reliable than SCSI?

Jay Nelson (
Tue, 19 Nov 1996 20:08:34 -0600 (CST)

Interesting question. I learned a long time ago -- about 1.2.28
(a.out) that IDE and SCSI didn't mix well -- particularly with a tape
drive on the SCSI bus. Is that because tapes can't
disconnect/reconnect? Can your CD writer? Or is it an INT 13 problem?

My problem was always on _reads_ from the tape and a hard reset was
generally the solution. I would _really_ appreciate someone explaining
how IDE, EIDE and SCSI can or can't work together.

Is tagged queueing part of the problem? (Free BSD, doesn't support it,
I think, and I had the same problem with it -- except it trashed the

-- Jay

On Mon, 18 Nov 1996, Hubert Mantel wrote:

->we used the following system for writing CDs:
->P100 with 32MB RAM, an EIDE hard drive and a 4x speed Yamaha CD-ROM writer
->with 8MB connected to a NCR53C810 SCSI adaptor. The system was very
->stable. We could compile a kernel, transfer another iso9660-image over the
->100MB net and write a CD at 4x speed without any problems. All
->Then the harddisk died and we modified the system. Now it's a P133 with
->32MB, and we replaced the disk with a SCSI disk connected to the same NCR
->controller to which the writer is connected. Lots of problems when writing
->CDs. So we inserted a second SCSI Adapter (DPT) and attached the hard disk
->to it. But still we may not "touch" the machine whilst writing a CD. There
->is only one device attached to every of the both SCSI adaptors! Besides of
->that, the system is absolutely reliable and rock solid even under highest
->Why is writing from an EIDE disk to the SCSI writer so much more reliable
->than writing from a SCSI disk to the writer? Any hints?
-> Hubert
->Oh, almost forgot: Kernel is 2.0.25 of course ;-) Same software on both

We are condemned to repeat history when we don't learn
because those who learn from history repeat it.