Chris Tyler - Fedora Linux

The Intel Preboot Execution Environment (PXE) specification is used for network booting of Fedora systems. The PXE boot process uses the pxelinux bootloader, which is retrieved from /tftpboot/linux-install/pxelinux.0 on the TFTP server. Once it is running, pxelinux searches for an appropriate configuration file in /tftpboot/linux-install/pxelinux.cfg , first trying for a file named with the hardware MAC address of the target system's Ethernet adapter, then a series of filenames generated from the target's IP address written in hexadecimal, and then finally the file default .

The system-config-netboot tool is executed when you select the menu option System→Administration→Server Settings→Network Booting Service. It creates a file in /tftpboot/linux-install/pxelinux.cfg named according to the network address specified in the GUI. For example, if the user specifies a certain configuration for the IP network 192.168.1, the configuration is stored in the file /tftpboot/linux-install/pxelinux.cfg/C0A801 because 192.168.1 in decimal corresponds to C0A801 in hexadecimal.

system-config-netboot obtains the pxelinux bootloader, Linux kernel, and initrd files from the specified network installation server (the pxelinux bootloader is found in the /images directory on the network installation server).

A network installation server is not intended to provide boot files for the installation, so its only purpose is to provide the package files and other information needed to install Fedora Core after the installation environment has loaded. While FTP, NFS, and HTTP are all available, NFS and FTP use multiple ports (NFS actually relies on multiple server programs), whereas HTTP uses a single server on a single port.

It is possible to install directly from a public Fedora Core HTTP or FTP mirror; simply enter the mirror URL as the server for the HTTP or FTP installation methods. However, doing so generates a lot of Internet traffic, resulting in a long installation time, and the likelihood of a network error aborting the entire installation partway through is higher than it would be on a local LAN. If you are going to install more than once, it's a better idea to download the files onto a local machine for speed.

The normal Fedora Core CD 1 is too large to fit on a mini-CD, but the boot image in /images/boot.iso on that CD (or the Fedora Core mirror servers) is under 8 MB in size and will easily fit on an 8 cm mini-CD or a "business card" CD.

Unfortunately, the Fedora Core installation boot files are now too large to fit on a 1.44 MB floppy disk. However, you may be able to use the 8 MB USB disk image file ( diskboot.img ) with a larger removable disk, such as a Zip or LS-120 disk.

Although system-config-netboot is recommended for PXE configuration, you can also use the pxeos and pxeboot commands to configure PXE from the command line.

To configure a version of Fedora Core for PXE booting:

# pxeos -a -i " Fedora Core 6 " -p HTTP -D 0 -s 192.168.1.2 -L /fedora fc6

These are the arguments used:

-a

Add to the existing configuration

-i " Fedora Core 6 "

The descriptive identification for this entry

-p HTTP

Installation protocol (can be HTTP , FTP , or NFS )

-D 0

Sets this up as an installation instead of a diskless boot

-s 192.168.1.2

The HTTP, FTP, or NFS server address

-L /fedora

The pathname on the server; in this example, the -p , -s , and -L options combine to be equivalent to http://192.168.1.2/fedora

fc6

The operating system identifier

To configure specific hosts to use the fc6 boot image:

# pxeboot -a -O fc6 192.168.1

This will configure all hosts that have an IP address beginning with 192.168.1 to use the fc6 configuration. To configure the use of a Kickstart file (see the next lab), add the option -K followed by the Kickstart URL.

 The manpages for dd , httpd , mkdosfs , rsync , wget , system-config-netboot , dhcpd , dhcpd.conf , tftpd , pxeos , and pxeboot

 The HTML documentation for system-config-netboot : file:///usr/share/doc/system-config-netboot-0.1.38/index.html

 The syslinux home page (which includes the isolinux and pxelinux bootloaders): http://syslinux.zytor.com/

 The Intel PXE specification: http://download.intel.com/design/archives/wfm/downloads/pxespec.pdf

In a normal Fedora Core installation, Anaconda asks a number of questions before beginning the actual installation procedure, which then runs without any user intervention (except for changing CDs, if that is the chosen installation method).

Kickstart is a Fedora installation option that uses a text file to supply basic configuration information so that Anaconda can skip all of the questions normally asked during installation.

To use Kickstart, you must create a Kickstart file using any regular text editor. A Kickstart file contains a number of options, one per line, with arguments.

These options are required:

auth or authconfig

Configures the authentication system. For normal password authentication, use the arguments --enableshadow --enablemd5 .

bootloader

The GRUB installation location and password. For an upgrade, use --upgrade ; for a new installation, use --location=mbr --md5pass= encryptedpassword (I cover how to generate encrypted passwords shortly).

lang

Selects the language to be used during installation. Possible values are listed in /usr/share/system-config-language/locale-list ; for U.S. English, use the argument en_US .

keyboard

The keyboard type to be used. Specify us for a standard North American English keyboard, or use one of the codes found in /usr/lib/python2.4/site-packages/rhpl/keyboard_models.py (such as cf for Canadian French).

rootpw

The root password. Use the arguments --iscrypted encryptedpassword .

timezone

The time zone for the system. The third column of /usr/share/zoneinfo/zone.tab lists possible values, such as America/Toronto or Asia/Shanghai . Add the argument --utc if the system clock is in UTC (recommended except when the system is dual-boot and you are in a time zone that has daylight savings time).

To encrypt a password for the bootloader and root access, use the openssl command:

$ openssl passwd -1 -salt " RaNDoMjuNk " " MySecretPassword "