rompub@gpu.utcs.utoronto.ca (Mark Dornfeld) (08/31/90)
I have purchased a Wren VI Harddisk for installation under SCO Xenix and/or SCO Unix ODT. The disk has 1747 cylindars, 7 head and 54 sectors/track. I am using an Everex ESDI controller that understands what this disk is all about and has routines to handle it. The SCO ODT documentation suggests that such a disk is compatible as long as the root partition doesn't cross over the 1024 cylindar boundary. Now, my limited understanding of disk geometry tells me that is not an easy task. Has anyone had any experience with this or similar drives under Xenix or Unix. Can it be used reliably? Mark T. Dornfeld Royal Ontario Museum Toronto, Ontario utgpu!rom!mark or utgpu!rompub Please reply via email and I will summarize and post. Thanks for any help in advance.
romkey@asylum.SF.CA.US (John Romkey) (09/02/90)
In article <1990Aug31.022148.5775@gpu.utcs.utoronto.ca> utgpu!rom!mark, utgpu!rompub writes: >Has anyone had any experience with this or similar drives under Xenix >or Unix. Can it be used reliably? I'm using a 1658 cylinder, 15 head ESDI disk with a WD1007SV-?? (can't remember those letters right now) disk controller under SCO Xenix with no problems; I can access the entire disk (no geometry remapping or anything). I hadn't heard about the root partition restriction, but that should be relatively easy to get around. I suspect the problem is that /boot reads in /xenix (or /unix) using BIOS routines, which probably won't be able to go beyond 1024 cylinders, so you have to guarantee that /xenix or /unix is entirely within the first 1024 cylinders. So, just make the root partition be less than 1024 cylinders long and you're set. Put other stuff like user accounts in partitions like /u. -- - john romkey USENET/UUCP: romkey@asylum.sf.ca.us Internet: romkey@ftp.com King Kong died for your sins.
art@pilikia.pegasus.com (Art Neilson) (09/03/90)
In article <1990Aug31.022148.5775@gpu.utcs.utoronto.ca> utgpu!rom!mark, utgpu!rompub writes: >I have purchased a Wren VI Harddisk for installation under SCO Xenix >and/or SCO Unix ODT. The disk has 1747 cylindars, 7 head and 54 >sectors/track. I am using an Everex ESDI controller that understands >what this disk is all about and has routines to handle it. > >The SCO ODT documentation suggests that such a disk is compatible as >long as the root partition doesn't cross over the 1024 cylindar >boundary. Now, my limited understanding of disk geometry tells me >that is not an easy task. > >Has anyone had any experience with this or similar drives under Xenix >or Unix. Can it be used reliably? You can either split your system into separate filesystems such that root doesn't cross the boundary, or turn on sector mapping in your controller. You can do this from DOS by going into debug and giving the command g=c800:5, note that some controllers may have their ROM at a different location, consult your controller docs. You should get some kinda menu with a choice for setting special options, one of the options should enable the controller to map the sectors such that it presents < 1024 cylinders to your OS. -- Arthur W. Neilson III | ARPA: art@pilikia.pegasus.com Bank of Hawaii Tech Support | UUCP: uunet!ucsd!nosc!pegasus!pilikia!art