Recently I got a laptop that came without CD or floppy. This laptop supports PXE boot so the only choice was to install Ubuntu over the network. In order to do that, I needed a DHCP server that supports PXE boot, tftp server and of course the boot file that will start the installation over the network. You can see my previous article on how to setup a DHCP server on OpenBSD. Installation of the tftp server is very easy on OpenBSD. You have to edit /etc/inetd.conf and uncomment the first entry for tftp.

ident           stream  tcp     nowait  _identd /usr/libexec/identd     identd -el
ident           stream  tcp6    nowait  _identd /usr/libexec/identd     identd -el
tftp            dgram   udp     wait    root    /usr/libexec/tftpd      tftpd -s /tftpboot
#tftp           dgram   udp6    wait    root    /usr/libexec/tftpd      tftpd -s /tftpboot

Now, you need to refresh inetd process and create the home/root folder for the tftp.

kill -HUP `cat /var/run/inetd.pid`
mkdir /tftpboot  

Make sure that tftp is working. Type q to exit.

tftp localhost
tftp> q

Next, you have to download the Ubuntu network installation file and place it in /tftpboot. Put this file in /tftpboot and unpack it with:

tar xzvf netboot.tar.gz

You have to change the MAC address in /etc/dhcpd.conf to match the MAC address on the computer where you want to install Ubuntu. Restart the computer, choose network boot and install.