Initio I/O HIGHWAY - Manual (Page 56)

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initio
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Troubleshooting
Consult the SCO UnixWare Installation Handbook “Troubleshooting” section to help
isolate the problem. If it becomes necessary to remove the Initio device driver,
please consult the “Removing the Initio Driver from a SCO UnixWare System”
section of this document.
B: DOS Space > 1GB
The default disk head mapping for Initio SCSI host adapter is 255 heads and 63 sectors.
This translates to a maximum accessible capacity of 8 GBytes per drive under MS-DOS.
Warning: If you have already installed the operating system on your hard drives,
changing the head mapping will corrupt your files and cause other unexpected prob-
lems. Before changing any “DOS Space > 1GB” option setting, please back up your disk
drives. Then you should run the FDISK utility to delete all the partitions on your selected
disk drive. At this point you can switch the setting, reinstall the operating system, and
restore your backed up files.
All device drivers for the INI-9100A Host Adapter will support different head mappings
based on the setting of “DOS Space > 1GB” option.
MS-DOS, OS/2 & Windows NT
Under MS-DOS, OS/2 & Windows NT, we recommend you enable “DOS Space > 1GB”
option if your SCSI hard disk has more than 1 GByte capacity.
SCO UNIX
SCO UNIX does not have a 1 GByte barrier. Therefore, the “DOS Space > 1GB” option is
not required to be enabled; however, you must make sure the root file system is located
below 1024 cylinders in order to perform the kernel boot routines. If the size of the root
file system is greater than 1 GByte or the location of root file system is beyond 1 GByte,
you should enable the “DOS Space > 1GB” option.
SCO UNIX can not support different head mappings for each disk drive under the same
host adapter. The head mapping will be based on the setting represented by target ID 0.