Novell ZENWORKS LINUX MANAGEMENT 7.2 IR2 - ADMINISTRATION GUIDE 09-25-2008, Руководство администратора

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322 Novell ZENworks 7.2 Linux Management Administration Guide
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Using Preboot Services, you can automatically place an image on a device, even if the device’s hard
disk is blank. You do not need to use the CD or DVD, or a ZENworks partition on the device.
28.2.2 Understanding the ZENworks NBPs
The Intel PXE specification defines mechanisms and protocols that allow PXE devices to use their
network interface cards (NICs) to find bootstrap programs located on network servers. In the PXE
specification, these programs are called Network Bootstrap Programs (NBPs).
NBPs are analogous to the bootstrap programs found in the Master Boot Records (MBRs) of other
boot media, such as hard drives, floppy disks, CDs, and DVDs. The purpose of a bootstrap program
is to find and load a bootable operating system. MBRs on traditional boot media accomplish this by
locating the necessary data on their respective media. NBPs accomplish this by using files found on
network servers, usually TFTP servers.
ZENworks Preboot Services uses two separate NBPs working together:
Š
“nvlnbp.sys” on page 322
Š “pxelinux.0” on page 322
nvlnbp.sys
This NBP has the following responsibilities:
Š
Detect various SMBIOS parameters and local hardware
Š Read the ZENworks identity information from the hard drives
Š
Communicate with novell-zmgprebootpolicy to determine if there is any preboot work
applicable to the device
Š
Present and manage the Preboot Services menu
Š
If necessary, launch
pxelinux.0
to execute the assigned preboot work
pxelinux.0
The primary purpose of this NBP is to load the operating system that is required to execute the
assigned preboot work.
The
pxelinux.0
file is a modified version of part of an open source project called syslinux.
Although
pxelinux.0
is primarily a Linux loader, it is capable of loading other operating
systems. It operates by using configuration files located on a TFTP server to provide boot
instructions. The various
pxelinux.0
configuration files used by Linux Management can be
found on your imaging server in the
/srv/tftp
directory.
In Linux Management, when PXE devices are assigned preboot work, they are also told which
pxelinux.0
configuration file they should use to execute that work. Similarly, when using the
Preboot Services Menu, each menu option corresponds to a
pxelinux.0
configuration file. For
more information, see Section 29.3.4, “Editing the Preboot Services Menu,” on page 368 .
For more information on
pxelinux.0
and its configuration files, see the syslinux home page
(http://syslinux.zytor.com/pxe.php) .
For a copy of the Novell modifications to the syslinux open-source project, see Novell Forge (http://
forge.novell.com) .