Building a Debian chroot image - Revision history

Ragingmind: Fixing some minor gramar oops-es and updating some wording to be more clear

2011-03-30T14:06:32Z

Fixing some minor gramar oops-es and updating some wording to be more clear

Ragingmind: updating dirctory names to be consistant

2011-03-30T02:29:29Z

updating dirctory names to be consistant

Ragingmind at 02:20, 30 March 2011

2011-03-30T02:20:54Z

Ragingmind: Created page with "I will fill this in within a few minutes."

2011-03-30T01:16:49Z

Created page with "I will fill this in within a few minutes."

New page

I will fill this in within a few minutes.

@@ Line 1: / Line 1: @@
-Having a custom image for your chroot can be quite handy especially if you would like to customize what comes pre-installed.  The following steps should work as-is on a Debian Squeeze system.  They should also work for Ubuntu, but the name of the qemu package that provides the necessary binary is different.  Please see [[Debian chroot]] for instruction on how to actually use this image on the Pre.
+Building your own image for a chroot can be quite handy especially if you would like to customize what comes pre-installed.  The following steps should work as-is on a Debian Squeeze system.  They should also work for Ubuntu, but the name of the qemu package that provides the necessary binary is different.  Please see [[Debian chroot]] for instruction on how to actually use this image on the Pre.
 Required packages: debootstrap, qemu-user-static, binfmt-support
 ==Creating the image file==
-Pick a directory to work in on your desktop/laptop computer.  All the commands are relative to the current directory so it shouldn't matter where, as long as you have write access.
+Pick a directory to work in on your desktop/laptop computer.  All the commands are relative to the current directory so it shouldn't matter where, so long as you have write access.
 <source lang="bash">
 dd if=/dev/zero of=DebianSqueeze_armel.img bs=1M count=512
@@ Line 10: / Line 10: @@
 </source>
-Now to put an ext2 file system in that blank file. '''The rest of these steps require being run at root.'''
+Now to put an ext2 file system in that blank file. '''The rest of these steps require being run as root.'''  Note the loop device output by the first command, it will probably be ''loop0'' and in the examples below this is what you'll put in for ''[device]''
 <source lang="bash">
 losetup -f
 losetup -f DebianSqueeze_armel.img
 mkfs.ext2 /dev/[device]
@@ Line 27: / Line 24: @@
 </source>
-At this point the system is only partially setup.  This next step would have to be preformed on the Pre, but with the help of qemu and binfmt we can do that on our desktop as well.
+At this point the system is only partially setup.  This next step with debootstrap would have to be preformed on the Pre, but with the help of qemu and binfmt we can do that on our desktop as well.
 <source lang="bash">
 cp /usr/bin/qemu-arm-static build/usr/bin/
@@ Line 41: / Line 38: @@
 </source>
-This next step is entirely optional and if you don't understand what it will do to the default choices made by apt when installing packages then I strongly recommend skipping it.  It is only useful to keep space usage down, but at the cost of functionality.
+This next step is entirely optional and if you don't understand what it will do to the default choices made by apt when installing packages then '''I strongly recommend skipping it'''.  It is only useful to keep space usage down, but at the cost of functionality.
 <source lang="bash">
 echo 'APT { Install-Recommends "false"; };' > /etc/apt/apt.conf.d/50no-recommends

@@ Line 24: / Line 24: @@
 <source lang="bash">
 mount /dev/[device] build/
-debootstrap --arch armel --foreign squeeze mnt/ http://ftp.us.debian.org/debian
+debootstrap --arch armel --foreign squeeze build/ http://ftp.us.debian.org/debian
 </source>
 At this point the system is only partially setup.  This next step would have to be preformed on the Pre, but with the help of qemu and binfmt we can do that on our desktop as well.
 <source lang="bash">
-cp /usr/bin/qemu-arm-static mnt/usr/bin/
+cp /usr/bin/qemu-arm-static build/usr/bin/
-chroot mnt/
+chroot build/
 /debootstrap/debootstrap --second-stage
 </source>
@@ Line 54: / Line 54: @@
 A few steps to clean up on your desktop.
 <source lang="bash">
-rm mnt/usr/bin/qemu-arm-static
+rm build/usr/bin/qemu-arm-static
-umount mnt/
+umount build/
 losetup -d /dev/[device]
 </source>

← Older revision		Revision as of 02:20, 30 March 2011
Line 1:		Line 1:
−	I will fill this ~~in within~~ a few ~~minutes~~.	+	Having a custom image for your chroot can be quite handy especially if you would like to customize what comes pre-installed. The following steps should work as-is on a Debian Squeeze system. They should also work for Ubuntu, but the name of the qemu package that provides the necessary binary is different. Please see [[Debian chroot]] for instruction on how to actually use this image on the Pre.
		+
		+	Required packages: debootstrap, qemu-user-static, binfmt-support
		+
		+	==Creating the image file==
		+	Pick a directory to work in on your desktop/laptop computer. All the commands are relative to the current directory so it shouldn't matter where, as long as you have write access.
		+	<source lang="bash">
		+	dd if=/dev/zero of=DebianSqueeze_armel.img bs=1M count=512
		+	mkdir build
		+	</source>
		+
		+	Now to put an ext2 file system in that blank file. '''The rest of these steps require being run at root.'''
		+	<source lang="bash">
		+	losetup -f
		+	</source>
		+	Note the loop device output by this, it will probably be loop0 and in the examples below this is what you'll put in for [device]
		+	<source lang="bash">
		+	losetup -f DebianSqueeze_armel.img
		+	mkfs.ext2 /dev/[device]
		+	</source>
		+
		+	==Building a system==
		+	Now we can fill the image with Magic cough I mean Debian 6.0.x "squeeze"
		+	<source lang="bash">
		+	mount /dev/[device] build/
		+	debootstrap --arch armel --foreign squeeze mnt/ http://ftp.us.debian.org/debian
		+	</source>
		+
		+	At this point the system is only partially setup. This next step would have to be preformed on the Pre, but with the help of qemu and binfmt we can do that on our desktop as well.
		+	<source lang="bash">
		+	cp /usr/bin/qemu-arm-static mnt/usr/bin/
		+	chroot mnt/
		+	/debootstrap/debootstrap --second-stage
		+	</source>
		+
		+	Now that the base system is installed and set up there is some minor housekeeping that we can do before transferring everything to the Pre. First we will clear apt's cache and then add a default mirror to sources.list
		+
		+	<source lang="bash">
		+	apt-get clean
		+	echo "deb http://ftp.us.debian.org/debian squeeze main" > /etc/apt/sources.list
		+	</source>
		+
		+	This next step is entirely optional and if you don't understand what it will do to the default choices made by apt when installing packages then I strongly recommend skipping it. It is only useful to keep space usage down, but at the cost of functionality.
		+	<source lang="bash">
		+	echo 'APT { Install-Recommends "false"; };' > /etc/apt/apt.conf.d/50no-recommends
		+	</source>
		+
		+	Exit the chroot
		+	<source lang="bash">
		+	exit
		+	</source>
		+
		+	==Cleaning up==
		+	A few steps to clean up on your desktop.
		+	<source lang="bash">
		+	rm mnt/usr/bin/qemu-arm-static
		+	umount mnt/
		+	losetup -d /dev/[device]
		+	</source>
		+
		+	==Tada!==
		+	Now you have an image of Debian Squeeze that you can use on your Pre. This is where you transfer the image to the USB drive and there are several ways to do that.
		+
		+	==More Resources==
		+	[http://wiki.debian.org/Debootstrap deboostrab on the debian wiki]
		+
		+	[http://wiki.debian.org/EmDebian/CrossDebootstrap information about cross debbootstrap on the debian wiki]
		+
		+	[http://www.digriz.org.uk/debootstrap-qemu helpful guide on digriz.org.uk]