on 6/16/00 2:26 PM, Matthew Reilly at mjreilly@inch.com wrote something
like:

> I previously posted about the Supermac C500/200 32MB, one Dayna 10BT (de)
> and one SMC 10/100 card (rtk) 2GB WD IDE disk & stock SCSI CD-ROM. I
> recently upgraded the 2GB IDE drive with a Seagate 4.3GB Barracuda. The
> upgrade went well until I unplugged the box to move it back into it's
> original position. It wouldn't boot off the IDE or the SCSI disk, I got the
> Default Catch! thing. I was pretty frustrated until I remember that I used
> the System Disk that came with my Darwin 0.3 disk. I booted from the CD ran
> system disk, ignored the message saying System Disk would have no effect on
> my machine and the fact the it didn't seem to make any changes to my OF
> settings. Back in OF I booted right off the SCSI disk no problems. The
> lesson is, even if System Disk isn't supposed to support your machine, give
> it a try if you are having booting problems.

Most interesting.

> That leads to my question. The Barracuda is much faster than the IDE disk it
> replaced but it is also louder, hotter and (I assume) draws more power. Is
> it possible to spin down a SCSI hard disk in NetBSD? I've done some
> searching but the only thing I've found relates to apm which, as far as I
> understand is a i386 thing. I'm running -current on my gateway box that does
> NAT and serves Appletalk volumes for myself and my GF's powerbook. I'd like
> to be able to spin down the disk over night or when I know the Appletalk
> volumes are not going to be used. Is this doable? Will the box still perform
> NAT with the root disk spun down?

    Yes nat will still run.

    No, I'm not exactly pleased with IDE performance on any platform. Ultra
66 sounds promising though. You think your Barracuda is fast now, you should
grab an add in SCSI card that can do Fast data transfer (10MB/S vs 5MB/s)
    As far as spinning disks down, yes it can be done. Using Apple's Energy
Saver control panel or FWB's SCSI Configure (Part of the full version of
HDT) can set a spin down timeout. However I have picked up from more than a
few people that you are better off *not* spinning your disk down ever. With
newer drives you end up putting more wear and tear on the drive spinning
down and powering up than if you just let it run 24/7.  Secondly, you're not
likely to get away with having the disk spin down in Unix. Sendmail does
it's thing at about 2 am, and various log files get turned over daily.
Unless you were to go through and remove every cron job, including
sync/update (<- This is NOT recommended); as well as turn off all daily
functions in daily.conf
    Even then your HD would probably be spinning up three or four times a
night. Unless you know the mode pages hex value and the value you want to
set it to in hex, I don't think you can set spin down timeout in NetBSD BTW.

    Chris