Red Hat NETWORK 3.3 - PROVISIONING, Справочное руководство

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64 Chapter 4. Red Hat Network Website
Warning
Since RHN Proxy Servers direct files from the central RHN Servers, and those servers do not dis-
tribute the files necessary for kickstart, systems connected to a Proxy not being served by an RHN
Satellite Server must be kickstarted using an external installation tree. Refer to Section 4.4.10.8
Distributions for instructions on setting up installation trees.
4.4.10.1. Kickstart Prerequisites
Although Red Hat Network has taken great pains to ease the provisioning of systems, some prepara-
tion is still required for your infrastructure to handle kickstarts. For instance, before creating kickstart
profiles, you should have:
•
Installed and have running a DHCP server.
•
Installed and have running a TFTP server.
•
Configured DHCP to assign required networking parameters and the bootloader program location.
•
Specified within the bootloader configuration file the kernel to be used and appropriate kernel op-
tions.
For a decription of the innerworkings of the kickstart process, refer to Section 4.4.10.2 Kickstart
Explained .
4.4.10.2. Kickstart Explained
When a machine is to receive a network-based kickstart, the following events must occur in this order:
1. After being placed on the network and turned on, the machine’s PXE logic broadcasts its MAC
address and a request to be discovered.
2. The DHCP server recognizes the discovery request and extends an offer of network information
needed for the new machine to boot. This includes an IP address, the default gateway to be used,
the netmask of the network, the IP address of the TFTP server holding the bootloader program,
and the full path and filename of that program (relative to the TFTP server’s root).
3. The machine applies the networking information and initiates a session with the TFTP server to
request the bootloader program.
4. The bootloader, once loaded, searches for its configuration file on the TFTP server from which it
was itself loaded. This file dictates which kernel and kernel options, such as the initial RAM disk
(initrd) image, should be executed on the booting machine. Assuming the bootloader program
is SYSLINUX, this file will be located in the
pxelinux.cfg
directory on the TFTP server and
named the hexadecimal equivalent of the new machine’s IP address. For example, a bootloader
configuration file for Red Hat Enterprise Linux AS 2.1 should contain:
port 0
prompt 0
timeout 1
default My_Label
label My_Label
kernel vmlinuz
append ks=http://myrhnsatellite/ initrd=initrd.img network apic
5. The machine accepts and uncompresses the init image and kernel, boots the kernel, and initiates
a kickstart installation with the options supplied in the bootloader configuration file, including
the server containing the kickstart configuration file.