User`s manual

GEVBOOT - Global Environment Variable Boot
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GEVBOOT - Global Environment Variable Boot
Command Input
GEVBOOT Variable-Name
Description
The GEVBOOT command permits the user to boot the system
using a Global Environment Variable, Variable-Name, which is a
Òfw-boot-pathÓ.
Background: Residual Data and Boot List
Recent releases of IBM AIX requires that the PRP style of residual
data be provided by the system firmware. Previous releases of
IBM's AIX did not require that residual data be implemented.
Residual data, basically, informs the operating system of the system
attributes (i.e., what devices are present, how are they configured,
are they bootable?, etc.). To some degree, it is an abstraction of the
hardware that the system firmware provides.
IBM has further defined what residual data should look like now.
This latest version of IBM AIX also requires that the system
firmware must support a boot list. This boot list contains a list of
bootable devices that the firmware utilizes to boot the system. This
boot list is housed within a Global Environment Variable (GEV).
The GEVs are kept in the PRP partition of NVRAM, more
specifically, the global environment variable area. Through this
GEV, the OS/user can configure the system for its boot device
selection policy.
This latest version of IBM AIX also requires that the system
firmware support the PRP style of network booting. The PRP style
of network boot treats the network boot image the same as a mass
storage (e.g., hard disk, floppy) boot image. The network boot
feature facilitates AIX network install manager (NIM) feature.