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104527 04/15/1994 01:59 PM 05/09/2001 05:25 AM
How to install UNIX, DOS and WindowsNT on the same computer.
install unix xenix dos mswindowsnt mswindowsNT partitions fails odt fdisk
SCO UNIX System V/386 Release 3.2 Operating System Version 4.x
SCO Open Systems Software Release 3.0 and earlier

          How to set up separate fdisk partitions for UNIX, DOS and Windows NT
          during the installation.

          The example below is provided only for assistance, in addition 
          to following the Operating System Administration manuals.

          For SCO UNIX Version 4.0, 4.1 and 4.2 and DOS 4.01, 5.0, 6.0 and 
          6.1, the order in which UNIX and DOS are installed is insignificant 
          as long as the fdisk partition for DOS operating systems is set up 
          during the installation of the first one of the two operating systems.
          The DOS partition must be the first partition on the hard disk.  
          Please note that this is not true for XENIX or earlier versions of 
          UNIX which can be installed only with DOS 3.3 and which require that
          DOS be installed first.  Also, the size of the DOS partition used to
          be limited to 32 MB or less but that has changed for SCO UNIX Version
          4.0.  It is always recommended to start the UNIX system partition at 
          the beginning of the next cylinder of the hard disk. 

          Install SCO UNIX Operating System first.  During UNIX installation, 
          when fdisk is invoked, set aside a large enough partition for DOS; 
          also leave an unused hard disk area where you will later install 
          Windows NT.  (Windows NT requires 75 MB free hard disk space to 

          UNIX Partition Information:

          Please note that beginning and end blocks will vary from
          installation to installation.

          Partition   Status    Type        Start   End     Size

          1           Inactive  DOS         1       179     179
          2           Active    UNIX        3403    11849   8447 

          After completing the UNIX installation, test the system by booting 
          up.  Then run fdisk and change the active partition from UNIX to DOS
          before taking down the UNIX operating system with the command:
          (The '#' sign indicates the command line prompt, do not type it in.)

          # shutdown -y -g0

          Install DOS at this point.  Use the FAT file system type.

          DOS partition information: 

          Partition   Status    Type       Volume Label Mbytes System

          1           A         PRI DOS                 5      FAT12
          2                     non-DOS                 235 

          After DOS is installed, install Windows NT on the unused hard disk
          area that was set aside during UNIX installation.  Boot up with 
          Windows NT boot diskette.  Windows NT will detect UNIX and DOS 
          partitions and set up the Windows NT Bootmanager if DOS is found 
          on the system during Windows NT Operating System installation.  For
          file system type, choose FAT or Windows NT file system type.

          After Windows NT installation has finished, test the system by 
          booting up.  From the Boot Manager Menu, choose Windows NT.  To 
          shut down the system, use the Windows NT menu 'system shutdown' 
          option.  Boot up again using The Boot Manager, this time to DOS.
          Run DOS fdisk and set UNIX as the active partition. 

          DOS partition information: 
          Partition   Status    Type       Volume Label Mbytes System

          1                     PRI DOS                 5      FAT12
          2           A         non-DOS                 235 
          3                     EXT DOS                 89

          UNIX Partition Information:

          Partition   Status    Type        Start   End     Size
          1           Inactive  DOS         1       179     179
          2           Active    UNIX        3403    11849   8447 
          3           Inactive  DOS (ext)   180     3374    3195

          The three operating systems are now installed and working.  At the
          UNIX boot prompt 'boot:', press <Return> if you want to run UNIX.
          Then type 'dos' and press <Return> for the Windows NT Boot Manager.
          From the Windows NT Boot Manager Menu, choose Windows NT or DOS.
          UNIX can't be added to Windows NT Boot Manager Menu as an option.

          For hardware and software incompatibility issues, see DOS README 
          files.  Also refer to the SCO UNIX Operating System Installation 
          Guide and the Windows NT System Guide and MS DOS manuals for 

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