Booting from Diskette

The user may load a specific version of DOS or an equivalent 8086 operating system into a VMB session directly from a bootable diskette, by specifying A: at the value for DOS_STARTUP_DRIVE under DOS Settings. Note that this may affect the way in which applications in the VMB session may access the diskette drives; see Preparing AUTOEXEC.BAT and CONFIG.SYS (Drive Letter Allocation and Access) for further discussion.

Here is an example using DOS 5:

  • From a system running DOS 5, format a diskette with the /s option.

  • Copy FSFILTER.SYS from the OS/2 V2.0 subdirectory \OS2\MDOS onto the diskette.

  • Create CONFIG.SYS and AUTOEXEC.BAT on the diskette.

    A sample CONFIG.SYS to use is as follows (OS/2 V2.0 is installed in E: drive in this example): 

    REM Load FSFILTER driver
DEVICE=A:FSFILTER.SYS
REM load the stub XMS and EMS memory drivers from OS2.
DEVICE=E:\OS2\MDOS\HIMEM.SYS
DEVICE=E:\OS2\MDOS\EMM386.SYS

    A sample AUTOEXEC.BAT to use is as follows: 

    @ECHO OFF
PROMPT $P$G
REM set the path to where the DOS files were copied
SET PATH=C:\DOS
SET COMSPEC=C:\DOS\COMMAND.COM
REM load the stub mouse driver from OS/2 V2.0
LH E:\OS2\MDOS\MOUSE

  • Create a DOS subdirectory on the hard disk and copy the real DOS files there.

  • Insert the DOS boot diskette in the A: drive.

  • Locate the Command Prompts folder. It is usually a folder in the OS/2 System icon on the Workplace Shell.

  • Open the Command Prompts folder.

  • Locate the DOS from drive A: icon and double click on it.

    The DOS_STARTUP_DRIVE setting of this icon is pre-set to the value A:.

    The user cannot specify "B:" or an external diskette drive as the startup drive. There may be situations where it is desired to boot from a 5¼ inch diskette; typically the B: drive on PS/2 systems. One way to do this is by creating an image of the diskette, then booting this image (See Booting from Diskette Image).

    If a 5¼ inch diskette must be booted directly for some reason, this is possible if drive remapping is supported by the system (such as a PS/2 Model 57, 90 or 95). Normally A: is Drive 0 (3½ inch), and B: is Drive 1 (5¼ inch, if fitted). To change this, run "Set Startup Sequence" from the reference diskette, and ensure Drive 1 appears before Drive 0. Then the 5¼ inch drive will become the A: drive.

    Some 5¼ inch drives (such as the IBM External 1.2MB drive and associated adapter) require a device driver, and are accessed as D: or higher. They cannot be specified as a startup drive, nor can they be readdressed as A:, but can be the source drive when creating a bootable image file.

    [Back: Mouse, EMS and XMS Support]
    [Next: Booting from Diskette Image]