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IGURE
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-OS D
OES
In the past, client PCs using remoteboot ROMs could boot in only one of two ways:
from a server-based boot image file or from their hard drives. The Pre-OS
approach is a hybrid; the centrally-booted operating system is not the ultimate
operating system but rather a temporary environment created for executing
management applications. Ultimately, clients exit the Pre-OS environment and
continue to boot from their local hard drive. Exiting the Pre-OS environment is
similar to executing a very soft Ctrl+Alt+Del where the PC continues to load the
OS on the hard disk.
This entire concept, which we call “Pre-OS managed booting”, or simply “Pre-OS”,
is based on existing MBA firmware capabilities, extended by any desktop
management agents contained in a special boot image file.
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The Pre-OS framework is essentially a DOS client with optional network
connectivity. The Pre-OS boot image is executed as a drive A: RAM disk residing in
extended memory.
Most Pre-OS environments use a network connection to map network drives.
Regular network drivers may be loaded from the Pre-OS image, and this in no way
affects the Pre-OS environment or RAM drive operation.
If any network login is needed during the Pre-OS phase, it is typically as a guest
user, so that the user is not prompted to provide login name or password
information.
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