We must configure our network's DHCP server to be sure to give an IP address to the computer netbooting, and to advertise the location of the PXE bootloader.

Here is an example for inspiration, written for the ISC DHCP server (package dhcp3-server) in the /etc/dhcp3/dhcpd.conf configuration file:

# Options DHCP spécifiques à Pxelinux:
option space pxelinux;
option pxelinux.magic      code 208 = string;
option pxelinux.configfile code 209 = text;
option pxelinux.pathprefix code 210 = text;
option pxelinux.reboottime code 211 = unsigned integer 32;


subnet 192.168.1.0 netmask 255.255.255.0 {   # 192.168.1.0/24

  # IP addresses available for guests
  range 192.168.1.100 192.168.1.149;

  # allow booting from the net
  allow bootp;

  # for net booting, server where the first file to be loaded (by TFTP
  # protocol) ("filename" following definition) lies : so the TFTP
  # server's name.
  next-server myserver;

  # net boot configuration for guests with a PXE client :
  if substring (option vendor-class-identifier, 0, 9) = "PXEClient" {
    # Note : all files for PXE are relatives to the TFTP server's root
    # path, as usually defined in /etc/inetd.conf.

    # PXE boot loader (first program to be loaded, by TFTP)
    filename "pxelinux.0";

    # describe some specific pxelinux's options through DHCP options :
    site-option-space "pxelinux";
    option pxelinux.magic f1:00:74:7e;
    if exists dhcp-parameter-request-list {
      # Always send the PXELINUX options (specified in hexadecimal)
      option dhcp-parameter-request-list = concat(option dhcp-parameter-request-list,d0,d1,d2,d3);
    }

    # For a PXE boot menu, different versions are available : simple
    # text, text with curses, graphic (VESA)
    #option pxelinux.configfile "pxelinux/config_simple";
    #option pxelinux.configfile "pxelinux/config_curses";
    option pxelinux.configfile "pxelinux/config_vesa";

    # automatically reboot after 10 minutes of no activity
    option pxelinux.reboottime 600;
  }
}

This serves the kernel and initial ramdisk to the system at run-time.

You should install the tftpd-hpa package. It can serve all files contained inside a root directory, usually /var/lib/tftpboot/, as defined with its -s option. To let it serve files inside /srv/debian-live/tftpboot, modify its start definition in /etc/inetd.conf with:

tftp           dgram   udp     wait    root  /usr/sbin/in.tftpd /usr/sbin/in.tftpd -s /srv/debian-live/tftpboot -r blksize -v -v

and reload the super server with /etc/init.d/openbsd-inetd reload.

Once the guest computer has downloaded and booted a Linux kernel and loaded its initrd, it will try to mount the Live filesystem image through a NFS server.

You should install the nfs-kernel-server package -- nfs-user-server does not function correctly with netboot.

Then, make the filesystem image available through NFS by adding a line like the following to /etc/exports:

/srv/debian-live *(ro,async,subtree_check,no_root_squash)

and tell the NFS server about this new export with the following command:

# exportfs -rv