How to make a minimal Debian EABI NFS root filesystem for an ARM host

Martin Guy, <martinwguy@yahoo.it>, 8 June 2008


This is not a shell script.

# 1. Make the root filesystem in a directory on a (Debian) host

# Optional: Set http proxy to use for package downloads
http_proxy="http://10.0.0.1:3128"
export http_proxy

# As root:
debootstrap --verbose --arch armel --foreign lenny /tftpboot/armel-lenny \
	 http://ftp.uk.debian.org/debian
cd /tftpboot/armel-lenny
mknod dev/console c 5 1

# Set package sources (for armel port)
echo 'deb http://ftp.uk.debian.org/debian lenny main' > etc/apt/sources.list

# Optional: Set http proxy the new system should use for package downloads
echo 'Acquire::http::Proxy "http://10.0.0.1:3128";' > etc/apt/apt.conf

# 2. Boot the board with this as its root filesystem passing init=/bin/sh
and on it go:

date 060814232008 	# Set the date (8 Jun 2008 14:23 UTC)
mount none /proc -t proc
export PATH		# It's set but it's not in the environment, der!
debootstrap/debootstrap --second-stage
# I found /proc unmounted at this point. Check it (ls /proc) and mount it if not.

rmdir debootstrap	# An empty dir was left for me. rm -r if not empty

cat /proc/mounts > /etc/fstab
vi /etc/fstab 
# delete:
	rootfs / rootfs rw 0 0
# and append:
	none		/proc	proc	defaults	0	0
# and if you have a local swap device (here a USB pendrive), something like:
	none		/tmp	tmpfs	defaults	0	0
	/dev/sda4	none	swap	defaults	0	0
# and in my case I have a shared /home
	10.0.0.1:/home	/home	nfs	defaults	0	0

Check /etc/resolv.conf is correct (it gets copied from the system you ran the
initial debootstrap on)

Edit /etc/hostname to whatever you want to call the host

Edit /etc/passwd and /etc/group if you need to.

Edit /etc/inittab, comment out the lines
	#1:2345:respawn:/sbin/getty 38400 tty1
	#2:23:respawn:/sbin/getty 38400 tty2
	#3:23:respawn:/sbin/getty 38400 tty3
	#4:23:respawn:/sbin/getty 38400 tty4
	#5:23:respawn:/sbin/getty 38400 tty5
	#6:23:respawn:/sbin/getty 38400 tty6
and append
	# TS-7250's serial port
	S0:23:respawn:/sbin/getty 115200 ttyAM0 vt102

# Enable root logins on the serial port
# (the device has a different name on ep93xx)
vi /etc/securetty
:/ttyS0/s//ttyAM0/
:wq

# Set timezone
ln -sf /usr/share/zoneinfo/Europe/London /etc/timezone

# Install some extra software from the net
apt-get install udev		# Necessary for correct operation of /dev
				# and to mount NFS volumes
apt-get install nfs-common	# Necessary to be able to mount nfs volumes
				# (/home in my setup)
apt-get install ssh procps	# For network logins, "ps" command etc

# Set the date from the network at boot time
apt-get install ntpdate		# To set the time&date precisely
vi /etc/init.d/rc.local	# and before the "exit 0", add the line:
	ntpdate pool.ntp.org
sh /etc/init.d/rc.local

# Finish
sync
exit	# exits single-user shell, halting the machine.
	# Alternatively, exec /sbin/init, then log in and reboot from there