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Fedora installation DVD ISO

Network of at least two machines

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These examples use Fedora Linux, but any Red Hat-derived distro should work. If you install to a removable medium, make sure that you have enough free space to make a copy of the installation DVD ISO. 16GB of free space is a sensible minimum.

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Make yourself root (type su into a terminal), then use YUM to add to extra packages with yum install dhcp tftp

tftp-server xinetd. You’re going to be

working as root, so, if you need to launch a GUI tool such as gedit, use sudo gedit (as root).

03

These examples use a machine with two network adaptors – one for connection to the outside world, and one to connect to the machines that need to boot from it. The second network card probably doesn’t have an IP address assigned yet, so we’ll set this via the GUI.

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DHCP assigns IP addresses and starts the boot process on clients. Visit the offi cial Fedora documentation (tinyurl.com/luad-dhcp) site to cut and paste an example DHCP confi guration for a boot server. Load the existing fi le (/etc/dhcp/dhcpd.conf) into a text editor.

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PXELINUX is the Linux bootloader that works over Ethernet. To get it, install SYSLINUX with yum install syslinux. The fi le we need is pxelinux.0. Copy it to the TFTP folder with cp /usr/share/syslinux/pxelinux.0 /var/

lib/tftpboot/. Type mkdir pxelinux.cfg to

create the confi guration directory.

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Right-click on the network icon and select Edit Connections…. Now locate the second adaptor, click on Edit and select the IPv4 Settings tab. Change the method from Automatic (DHCP) to Manual. Add a static IP address for your adaptor. For example, if your fi rst adaptor is on 10.0.1.1, adding the second adaptor with an address of 10.0.5.1 and a netmask of 255.255.255.0 will give you space to connect up to 255 machines to the boot server.

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TFPT is a basic fi le transfer protocol that the NIC fi rmware uses to fetch the bootloader. Load /etc/xinetd.d/tftp and change the line disable = yes so that it reads disable = no. TFTPD is managed by xinetd, so start with

systemctl start xinetd.service.

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Modify the example dhcpd.conf to match your network. The subnet for our example would be changed to 10.0.5.0, and routers is the same address as your second network adaptor. Setting range dynamic-bootp to 10.0.5.50 10.0.5.100; gives space for 50 machines. The parameter next-server should be set to the same address as your second network adaptor. Change fi lename "linux-install/

pxelinux.0"; to fi lename "pxelinux.0"; Save the fi le and then start the server with systemctl start dhcpd.service.

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Create two directories: /var/www/fedora and /media/loop. Copy the Fedora DVD ISO image to the current directory and type mount

-o loop -t iso9660 [path to ISO] /media/

loop. Use rsync to copy the fi les: rsync -v -a

-H /media/loop/ /media/var/www/fedora.

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Enter the BIOS setup screen of a client PC and make sure that the boot order specifi es network booting as the priority. When carrying out the installation, you will disconnect the router/switch from the internet and connect it to the boot server instead.

10

Add Apache 2 with the yum install

httpd command, and start it with systemctl

start httpd.service. Test that it is up

and running by navigating a web browser to http://10.0.5.1. If everything’s working, you

should see the Apache startup page.

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Firewall

Open the Firewall confi guration application. Select persistent confi guration. Add http, https, tftp and tftpclient to the list of trusted services. Select Reload fi rewalld from the Options menu.

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Type cd /var/lib/tftpboot/. Make a directory with mkdir pxelinux.cfg. Within this directory, create a text fi le called default. Add the following lines DEFAULT netinstall,

LABEL netinstall, kernel vmlinuz, append initrd=initrd.img repo=http://10.0.5.1/fedora/, implicit 1 and prompt 1 so that it looks like the

picture above. If you’re feeling adventurous, try adding prompt 0 so that clients won’t wait for user confi rmation before beginning the install. Be careful with that option!

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Enter the directory that TFTP can see with cd /var/lib/tftpboot/. Execute

wget http://10.0.5.1/fedora/isolinux/

vmlinuz. Copying the fi le like this makes a good

test that the server is working. Now retrieve initrd.img from the same directory.

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You must specify a root password using

the rootpw command to avoid a prompt. You

may want the installer to erase all partitions (or preserve some). The upgrade command causes the installer to upgrade the targets rather than carry out a fresh install.

Save your custom Kickstart fi le as /var/www/html/fedora/ks.cfg and then add ks=http://10.0.5.1/fedora/ks.cfg to the append line in your default fi le. By default, the fi nished target machines will begin in fi rst-run mode and ask the user to specify details such as username and password on the fi rst run.

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If the client tries but fails to load a fi le called pxlinux.0, it is communicating with DHCP, but TFTP may not be working. Try using the command tftp 10.5.0.1 -c get

pxelinux.0 on the server. If this retrieves

the fi le, try executing it again on another machine. If the installer begins to boot, can fi nd pxelinux.0, vmlinuz and initrd.img but stops at that point, try retrieving one of the fi les in /var/ www/http/fedora/ manually by using the wget

10.0.5.1/fedora/[name of file] command.

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Control Fedora services with

systemctl [command] [service]. The main

commands you’ll need are start, enable

to make permanent, and restart when you make confi guration changes. This project requires running httpd.service, dhcpd.service and xinetd.service.

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A Kickstart fi le supplies the installer with answers to avoid prompting the user. To begin, create a fi le called ks.cfg in /var/ www/html/fedora/. Go to the offi cial Fedora Anaconda/Kickstart page for a complete list of commands (tinyurl.com/luad-kickstart). When a Fedora system has been successfully installed, a (fully commented) Kickstart fi le is deposited in /root/anaconda-ks.cfg; this makes a good starting point for building your own. If you installed via the ISO, remove the line that sets install type to CDROM.

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