Tonight I installed my first diskless Ubuntu system. The version I used is the latest available as of today, 7.04 "FeistyFawn". This article covers the client part.
My other diskless machines all run Gentoo (for the time being). I've described previously
how I set up my SB 100, the rest of the setup was based on
this article.
The following two articles were helpful:
https://help.ubuntu.com/community/Installation/OnNFSDrive
http://developer.novell.com/wiki/index.php/Feisty/HOWTO:_Convert_Ubuntu_to_Diskless
However I found some of the info to be uncomplete or outdated.
From what I have read, unlike with Gentoo, it seems that there is no easy way to get a working diskless Ubuntu system directly. Instead, you have to install to a disk first, and then make your setup diskless. I did not really want to open the box, so I tried first to install on a 2 GB CF card, which didn't work because the card was full before the install completed (du now reports that the system is 2.1 GB big). So I ended up putting a disk in the box, and I ran a regular install.
Note: As in the SB100 article, 10.0.0.10 will be my dhcp/nfs/tftp server ('fileserver'). 10.0.0.30 will be the Ubuntu desktop.
Once that was completed, instead of rebooting as suggested by the installer, I opened a shell (gnome-terminal), and ran:
sudo su -
mkdir /mnt/tmp
mkdir /mnt/nfs
mount /dev/sda1 /mnt/tmp
mount 10.0.0.10:/diskless/ubuntu /mnt/nfs
cp -a /mnt/tmp/* /mnt/nfs/
After that, there are just a couple of things that need to be changed:
chroot /mnt/nfs
mount -t proc proc proc
vi etc/initramfs-tools/initramfs.conf
and make sure you have:
BOOT=nfs
then run:
update-initramfs -u
Now check what you have in /boot, and update your network boot config files accordingly. I use pxegrub, and here is how /boot/grub.lst looks like:
default 0
timeout 10
title=Diskless Ubuntu
root (nd)
kernel /diskless/tv/boot/vmlinuz-2.6.20-15-generic ip=dhcp root=/dev/nfs nfsroot=10.0.0.10:/diskless/tv ro quiet splash
initrd /diskless/tv/boot/initrd.img-2.6.20-15-generic
Finally, don't forget to update etc/fstab and etc/network/interfaces. I've read several theories, here is what worked for me:
fstab:
# /etc/fstab: static file system information.
#
#
proc /proc proc defaults 0 0
/dev/nfs / nfs defaults 0 0
/dev/scd0 /media/cdrom0 udf,iso9660 user,noauto 0 0
network/interfaces:
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet static
address 10.0.0.30
netmask 255.255.255.0
network 10.0.0.0
broadcast 10.0.0.255
gateway 10.0.0.1
(note: commenting out eth0 as suggested in some places made the system hang during the boot process.)
