Installing Ubuntu 11.04 (Natty Narwhal) on a ThinkPad X220

I installed Ubuntu 11.04 (Natty Narwhal) on a ThinkPad X220.

As a source of network installation files I made use of another GNU/Linux computer on my home LAN which is connected to the Internet through a familiar ADSL-modem/gateway/router/caching nameserver/DHCP server (call it "the gateway") at address 172.19.3.1. The gateway's DHCP server issues leases in the range 172.19.3.2 to 172.19.3.100.

First I set up the "source" machine, in my case one which already also had Ubuntu 11.04 installed. It has address 172.19.3.7 (assigned to it by the gateway's DHCP server). For the X220 to boot from it the machine needs to run a DHCP server and a TFTP server. The DHCP server serves only this special purpose since, as I mentioned, the gateway is the network's main DHCP server. The source's DHCP server must be so configured that it doesn't conflict with the existing DHCP server.

Install the isc-dhcp-server package and edit /etc/dhcp/dhcpd.conf using the following as a model.

ddns-update-style none;
option domain-name-servers 172.19.3.1;  # This is the address of my gateway
option routers 172.19.3.1;              # This is the address of my gateway
option subnet-mask 255.255.0.0;         # This is the netmask of my home network
default-lease-time 600;
max-lease-time 7200;
allow booting;
allow bootp;

subnet 172.19.3.0 netmask 255.255.255.0 {
  range 172.19.3.220 172.19.3.229;      # This is a range separate from the one used by the gateway and includes the address below
}

group {
  next-server 172.19.3.7;               # This is the address of the "source"
  host trawsfynydd {                    # 'trawsfynydd' is the name I chose for the X220
    hardware ethernet f0:de:f1:6b:22:bf; # This is the Ethernet address of the X220
    fixed-address 172.19.3.220;         # This is an address in the range as defined above
    filename "/pxelinux.0";
  }
}

Now install the tftpd-hpa package, download the network installation tarball and untar it into the location whence tftpd serves files.

$ cd /tmp
$ wget http://archive.ubuntu.com/ubuntu/dists/natty/main/installer-amd64/current/images/netboot/netboot.tar.gz
$ cd /var/lib/tftpboot
$ sudo tar zxf /tmp/netboot.tar.gz

Second set up the X220 for PXE (Pre-boot eXecution Environment).

• Switch on the X220 and press F1. ThinkPad Setup starts.
• Set Config | Network | Ethernet LAN Option ROM to "Enabled".
• Select Startup | Boot; select "PCI LAN IBA GE Slot..." and use the [+] key to move it to the top of the boot priority order
• Press F10 to save and exit.

Voilà, the X220 boots the Ubuntu installer.