Chapter 4. Obtaining System Installation Media 4.3. Preparing Files for TFTP Net Booting 4.3.1. Setting up RARP server 4.3.2. Setting up a DHCP server If your machine is connected to a local area network, you may be able to boot it over the network from another machine, using TFTP. If you intend to boot the installation system from another machine, the boot files will need to be placed in specific locations on that machine, and the machine configured to support booting of your specific machine. You need to set up a TFTP server, and for many machines a DHCP server, or RARP server, or BOOTP server. The Reverse Address Resolution Protocol (RARP) is one way to tell your client what IP address to use for itself. Another way is to use the BOOTP protocol. BOOTP is an IP protocol that informs a computer of its IP address and where on the network to obtain a boot image. The DHCP (Dynamic Host Configuration Protocol) is a more flexible, backwards-compatible extension of BOOTP. Some systems can only be configured via DHCP. The Trivial File Transfer Protocol (TFTP) is used to serve the boot image to the client. Theoretically, any server, on any platform, which implements these protocols, may be used. In the examples in this section, we shall provide commands for SunOS 4.x, SunOS 5.x (a.k.a. Solaris), and GNU/Linux. To set up RARP, you need to know the Ethernet address (a.k.a. the MAC address) of the client com- puters to be installed. If you don’t know this information, you can boot into “Rescue” mode (e.g., from the rescue floppy) and use the command ip addr show dev eth0 . On a RARP server system using a Linux kernel or Solaris/SunOS, you use the rarpd program. You need to ensure that the Ethernet hardware address for the client is listed in the “ethers” database (either in the /etc/ethers file, or via NIS/NIS+) and in the “hosts” database. Then you need to start the RARP daemon. Issue the command (as root): /usr/sbin/rarpd -a on most Linux systems and SunOS 5 (Solaris 2), /usr/sbin/in.rarpd -a on some other Linux systems, or /usr/etc/rarpd -a in SunOS 4 (Solaris 1). One free software DHCP server is ISC dhcpd . For Ubuntu, the isc-dhcp-server package is rec- ommended. Here is a sample configuration file for it (see /etc/dhcp/dhcpd.conf ): option domain-name "example.com"; option domain-name-servers ns1.example.com; option subnet-mask 255.255.255.0; default-lease-time 600; max-lease-time 7200; server-name "servername"; subnet 192.168.1.0 netmask 255.255.255.0 { range 192.168.1.200 192.168.1.253; option routers 192.168.1.1; } host clientname { filename "/tftpboot.img"; server-name "servername"; next-server servername; 24