Provided by: vmdebootstrap_1.9-1_amd64 
NAME
vmdebootstrap - install basic Debian system into virtual disk image
PURPOSE
vmdebootstrap is a helper to install basic Debian system into virtual disk image. It wraps debootstrap.
You need to run vmdebootstrap as root. If the --verbose option is not used, no output will be sent to the
command line. If the --log option is not used, no output will be sent to any log files either.
To use the image, you probably want to create a virtual machine using your preferred virtualization
technology, such as kvm or qemu. Configure the virtual machine to use the image you've created. Then
start the virtual machine and log into it via its console to configure it. The image has an empty root
password and will not have networking configured by default. Set the root password before you configure
networking.
SYNOPSIS
$ sudo vmdebootstrap --image=FILE --size=SIZE [--mirror=URL] [--distribution=NAME]
Options
--output=FILE
write output to FILE, instead of standard output
--verbose
report what is going on
--no-verbose
opposite of --verbose
--image=FILE
put created disk image in FILE
--size=SIZE
create a disk image of size SIZE (1000000000) in bytes. Suffixes k,K,M,G,T are supported, see
qemu-img(1) for more detail.
--tarball=FILE
tar up the disk's contents in FILE
--mirror=URL
use MIRROR as package source (http://httpredir.debian.org/debian/)
--arch=ARCH
architecture to use (amd64) --- if using an architecture which the host system cannot execute,
ensure the --foreign option is also used.
--distribution=NAME
release to use (defaults to stable). The release needs to be a valid Debian or Ubuntu release
name or codename.
--debootstrapopts=OPTS
Supply options and arguments to debootstrap, separated by spaces. e.g.
--debootstrapopts="variant=buildd no-check-gpg components=main,contrib". See debootstrap (1)
for more information. This option replaces the --variant support in previous versions.
--debootstrap-scripts=DIR
set the directory containing debootstrap scripts.
--package=PACKAGE
install PACKAGE onto system
--custom-package=DEB
install package in DEB file onto system (not from mirror) - all dependencies must be available
in the specified distribution.
--no-kernel
do not install a linux package
--kernel-package=PACKAGE
If --no-kernel is not used and the auto-selection of the linux-image-586 or linux-image-armmp
or linux-image-$ARCH package is not suitable, the kernel PACKAGE name can be specified
explicitly.
--enable-dhcp
enable DHCP on eth0
--root-password=PASSWORD
set root password
--lock-root-password
lock root account so they cannot login?
--customize=SCRIPT
run SCRIPT after setting up system. If the script does not exist in the current working
directory, /usr/share/vmdebootstrap/examples/ will be checked as a fallback. The script needs
to be executable and is passed the root directory of the debootstrap and the image name as the
only arguments. Use chroot if you need to execute binaries within the chroot created by
debootstrap.
--hostname=HOSTNAME
set name to HOSTNAME (debian)
--user=USERSTRING
create USER with PASSWORD. The USERSTRING needs to be of the format: USER/PASSSWORD.
--owner=OWNER
change the owner of the final image from root to the specified user.
--serial-console
configure image to use a serial console (Wheezy only)
--serial-console-command
(Wheezy only.) Set the command to manage the serial console which will be appended to
/etc/inittab. Default is /sbin/getty \-L ttyS0 115200 vt100, resulting in a line:
"S0:23:respawn:/sbin/getty \-L ttyS0 115200 vt100"
--sudo install sudo, and if user is created, add them to sudo group
--bootsize=BOOTSIZE
If specified, create a /boot partition of the given size within the image. Debootstrapping will
fail if this is too small for the selected kernel package and upgrading such a kernel package
is likely to need two or three times the space of the installed kernel.
--boottype=FSTYPE
Filesystem to use for the /boot partition. (default ext2)
--bootflag=FLAG
Flag to set on the first partition. (default none)
--bootoffset=SIZE
Space to leave at start of the image for bootloader
--roottype=FSTYPE
Filesystem to use for the / (root) partition. (default ext4)
--part-type=PART-TYPE
Partition type to use for this image. (default msdos)
--swap=SWAPSIZE
If specified, create a swap partition of the given size within the image. Debootstrapping will
fail if this results in a root partition which is too small for the selected packages. The
minimum swap space is 256MB as the default memory allocation of QEMU is 128MB. A default 1GB
image is not likely to have enough space for a swap partition as well.
--foreign=PATH
Path to the binfmt_handler to enable foreign support in debootstrap. e.g.
/usr/bin/qemu-arm-static Note: foreign debootstraps may take a significant amount of time to
complete and debootstrap will retry five times if packages fail to install by default.
--use-uefi
Setup image for UEFI boot
--no-use-uefi
opposite of --use-uefi
--esp-size=SIZE
Size of EFI System Partition - requires use-uefi
--extlinux
install extlinux (deprecated: default will change in a future release to use grub)
--no-extlinux
Skip installation of extlinux. Needs grub, a customize script or alternative bootloader to make
the image bootable. extlinux is deprecated and this will become the default in a future
release.
--mbr Run install-mbr (default if extlinux used)
--no-mbr
opposite of --mbr
--squash=DIRECTORY
Run mksquashfs against the rootfs using xz compression --- requires squashfs-tools to be
installed. The squashfs and other files needed to use the squashfs to make a bootable system
will be put into the specified directory. The directory will contain a filesystem.squashfs as
well as the top level contents of the boot/ directory. (If using UEFI, the boot/efi directory
as well.) By default, mksquashfs is allowed to use all processors which may result in high
load. squashfs can also have issues with large root filesystems. These errors can result in
truncated files. This is a known bug in squashfs. vmdebootstrap will fail if the squashed
filesystem is less than 1MB.
--configure-apt
Use the specified mirror and distribution to create a suitable apt source inside the VM. Can be
useful if debootstrap fails to create it automatically.
--apt-mirror
Use the specified mirror inside the image instead of the mirror used to build the image. This
is useful if you have a local mirror to make building the image quicker but the image needs to
run even if that mirror is not available. Requires --configure-apt
--grub Disable extlinux installation and configure grub2 instead. grub2 will be added to the list of
packages to install. update-grub will be called once the debootstrap is complete and
grub-install will be called in the image.
--no-acpid
Disable installation of acpid if not required, otherwise acpid will be installed if --foreign
is not used.
--sparse
Skip optimizing image for compression and keep a sparse image.
--no-sparse
opposite of --sparse
--pkglist
Output a list of package names installed inside the image. Useful if you need to track the
relevant source packages used inside the image for licence compliance.
--dry-run
Do not build, just test that the options are valid.
--no-update-initramfs
Skip the call to update-initramfs for reasons of speed or practicality.
--convert-qcow2
Convert the final raw image to qcow2 format.
--systemd-networkd
Use Predictable Network Interface Names
--no-systemd-networkd
Do not use Predictable Network Interface Names using systemd-networkd.
CONFIGURATION FILES AND SETTINGS
--dump-config
write out the entire current configuration
--no-default-configs
clear list of configuration files to read
--config=FILE
add FILE to config files
LOGGING
--log=FILE
write log entries to FILE (default is to not write log files at all); use "syslog" to log to
system log, or "none" to disable logging.
--log-level=LEVEL
log at LEVEL, one of debug, info, warning, error, critical, fatal (default: debug).
--log-max=SIZE
rotate logs larger than SIZE, zero for never (default: 0)
--log-keep=N
keep last N logs (10)
--log-mode=MODE
set permissions of new log files to MODE (octal; default 0600)
PERFORMANCE
--dump-memory-profile=METHOD
make memory profiling dumps using METHOD, which is one of: none, simple, meliae, or heapy
(default: simple)
--memory-dump-interval=SECONDS
make memory profiling dumps at least SECONDS apart
NETWORKING
Wheezy support
The --enable-networking option uses the /etc/network/interfaces.d/ source directory, with the default
settings for lo and eth0 being added to /etc/network/interfaces.d/setup. Other networking configuration
can be specified using a customisation script. Localhost settings would be:
auto lo
iface lo inet loopback
If --enable-dhcp is specified, these settings are also included into /etc/network/interfaces.d/setup:
auto eth0
iface eth0 inet dhcp
In addition, wheezy images do not boot if the roottype is specified as the default of ext4, so
vmdebootstrap will fail if a --roottype is not specified or is specified as ext4.
Jessie and later
In addition, systemd in jessie or later introduces PredictableNetworkInterfaceNames which are enabled
using the systemd-networkd service. If this option is disabled, traditional interface names (like eth0)
will be used and the predictable names masked using udev. Implementing the mask requires updating the
initramfs, so the --update-initramfs option must not be disabled.
If DHCP is also enabled, the following configuration is used:
/etc/systemd/network/99-dhcp.network
systemd will use the first available match, so this can be overridden by putting another file into place
using the customisation scripts, using a lower sorting filename.
Stretch and later
There is no need to use the --enable-dhcp option when using systemd for networking with stretch or sid.
systemd-resolved is enabled instead if systemd-networkd is specified. (--enable-dhcp would simply add an
unused entry to /etc/network/interfaces for eth0.)
[Match]
Name=en*
[Network]
DHCP=yes
BOOTLOADERS
Unless the --no-extlinux or --grub options are specified, the image will use extlinux as a boot loader.
bootsize is not recommended when using extlinux --- use grub instead.
NOTE:
Unlike grub, extlinux support requires the installation of packages outside the image which are used
to install the extlinux bootloader inside the image. extlinux support also involves the use of sync
which can cause issues on systems with multiple filesystems mounted, particularly over a network or
when building multiple images simultaneously. Therefore, extlinux is deprecated in vmdebootstrap. The
default will change in a future release and extlinux support may be dropped once Stretch is released.
extlinux support issues with ext4
VMs using ext4 may not boot when using extlinux - unless the build is performed on Jessie. Builds using
ext2 and ext3 work normally.
IMPORTANT:
This problem depends on the external distribution, not the distribution you are trying to build. When
building on Jessie, extlinux succeeds but when building on Stretch or Sid, extlinux fails to make a
bootable system if the filesystem of that system is ext4. ext2 and ext3 work.
Version 1.6 of vmdebootstrap adds a warning but allows the build to proceed (to allow for the bug to be
fixed). Sadly, downgrading the version of extlinux to the version in Jessie does not fix the problem when
building on stretch or sid. Hence, vmdebootstrap can only output a warning.
SEE ALSO:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=833057
Versions of grub2 in wheezy
Grub2 in wheezy can fail to install in the VM, at which point vmdebootstrap will fall back to extlinux.
It may still be possible to complete the installation of grub2 after booting the VM as the problem may be
related to the need to use loopback devices during the grub-install operation. Details of the error will
appear in the vmdebootstrap log file, if enabled with the --log option.
NOTE:
grub-legacy is not supported.
vmdebootstrap also supports EFI. See UEFI.
Use --use-uefi to use grub-efi instead of grub-pc. If the default 5MB is not enough space, use the
--esp-size option to specify a different size for the EFI partition. Registered firmware is not supported
as it would need to be done after boot. If the system you are creating is for more than just a VM or live
image, you will likely need a larger ESP, up to 500MB.
UEFI
UEFI support requires Grub and vmdebootstrap contains a configuration table of the UEFI components
required for supported architectures.
There are issues with running UEFI with QEMU on some architectures and a customisation script is
available for amd64:
# vmdebootstrap --verbose --image jessie-uefi.img --grub --use-uefi \
--customize ./examples/qemu-efi-bochs-drm.sh
vmdebootstrap supports UEFI for images and for squashfs but the necessary behaviour is different. With an
image, an ESP vfat partition is created. With squashfs, the EFI files will be copied into an efi/
directory in the squashfs output directory instead.
There is EFI firmware available to use with QEMU when testing images built using the UEFI support, but
this software is in Debian non-free due to patent concerns. If you choose to install ovmf to test UEFI
builds, a secondary change is also needed to symlink the provided OVMF.fd to the file required by QEMU:
bios-256k.bin and then tell QEMU about the location of this file with the -L option:
$ qemu-system-x86_64 -L /usr/share/ovmf/ -machine accel=kvm \
-m 4096 -smp 2 -drive format=raw,file=test.img
To test the image, also consider using the qemu-wrapper.sh:
$ /usr/share/vmdebootstrap/qemu-wrapper.sh jessie-uefi.img amd64 /usr/share/ovmf/
UBoot
UBoot needs manual configuration via the customisation hook scripts, typically support requires adding
u-boot using --package and then copying or manipulating the relevant u-boot files in the customisation
script. Examples are included for beaglebone-black.
Some u-boot examples recommend the use of the lba flag on the boot partition, so use the --bootflag
option where relevant.
INSTALLATION IMAGES AND VIRTUAL MACHINES
:file:vmdebootstrap is aimed principally at creating virtual machines, not installers or prebuilt
installation images. It is possible to create prebuilt installation images for some devices but this
depends on the specific device. (A 'prebuilt installation image' is a single image file which can be
written to physical media in a single operation and which allows the device to boot directly into a fully
installed system --- in a similar way to how a virtual machine would behave.)
vmdebootstrap assumes that all operations take place on a local image file or directory, not a physical
block device / removable media.
vmdebootstrap is intended to be used with tools like qemu on the command line to launch a new virtual
machine. Not all devices have virtualisation support in hardware.
This has implications for u-boot support in some cases. If the device can support reading the bootloader
from a known partition, like the beaglebone-black, then vmdebootstrap can provide space for the
bootloader and the image will work as a prebuilt installation image. If the device expects that the
bootloader exists at a specific offset and therefore requires that the bootloader is written as an image
not as a binary which can be copied into an existing partition, vmdebootstrap is unable to include that
bootloader image into the virtual machine image.
The beagleboneblack.sh script in the examples/ directory provides a worked example to create a prebuilt
installation image. However, the beagleboneblack itself does not support virtualisation in hardware, so
is unable to launch a virtual machine. Other devices, like the Cubietruck or Wandboard need u-boot at a
predefined offset but can launch a virtual machine using qemu, so the cubietruck and wandboard6q scripts
in the examples/ directory relate to building images for virtual machines once the device is already
installed and booted into a suitable kernel.
It is possible to wrap vmdebootstrap in such a way as to prepare a physical block device with a
bootloader image and then deploy the bootstrap on top. However, this does require physical media to be
inserted and removed each time the wrapper is executed. To do this, use the --tarball option instead of
the --image option. Then setup the physical media and bootloader image manually, as required for the
device, redefine the partitions to make space for the rootfs, create a filesystem on the physical media
and unpack the vmdebootstrap tarball onto that filesystem. Once you have working media, an image can be
created using dd to read back from the media to an image file, allowing other media to be written with a
single image file.
EXAMPLE
To create an image for the stable release of Debian:
sudo vmdebootstrap --image test.img --size 1G \
--log test.log --log-level debug --verbose \
--mirror http://mirror.lan/debian/
To run the test image, make sure it is writeable. Use the --owner option to set mode 0644 for the
specified user or use chmod manually:
sudo chmod a+w ./test.img
If --log is also used, consider using --log-mode as well so that the logfile is readable by the owner. By
default, the log file permissions are 0o600. The logfile itself will be owned by root.
Execute using qemu, e.g. on amd64 using qemu-system-x86_64:
qemu-system-x86_64 -drive format=raw,file=./test.img
(This loads the image in a new window.) Note the use of -drive file=<img>,format=raw which is needed for
newer versions of QEMU.
There is a bin/qemu-wrapper.sh <image> <arch> script for simple calls where the --owner option is used,
e.g.:
$ /usr/share/vmdebootstrap/qemu-wrapper.sh jessie.img amd64
There is EFI firmware available to use with QEMU when testing images built using the UEFI support, but
this software is in Debian non-free due to patent concerns. If you choose to install ovmf to test UEFI
builds, a secondary change is also needed to symlink the provided OVMF.fd to the file required by QEMU:
bios-256k.bin and then tell QEMU about the location of this file with the -L option:
$ qemu-system-x86_64 -L /usr/share/ovmf/ -machine accel=kvm \
-m 4096 -smp 2 -drive format=raw,file=test.img
To use the -nographic option, ensure that the --serial-console option is supplied to vmdebootstrap and
use -monitor none when booting the image with QEMU.
For further examples, including u-boot support for beaglebone-black, see
/usr/share/vmdebootstrap/examples
NOTES
If you get problems with the bootstrap process, run a similar bootstrap call directly and chroot into the
directory to investigate the failure. The actual debootstrap call is part of the vmdebootstrap logfile.
The debootstrap logfile, if any, will be copied into your current working directory on error.
debootstrap will download all the apt archive files into the apt cache and does not remove them before
starting the configuration of the packages. This can mean that debootstrap can fail due to a lack of
space on the device if the VM size is small. vmdebootstrap cleans up the apt cache once debootstrap has
finished but this doesn't help if the package unpack or configuration steps use up all of the space in
the meantime. Avoid this problem by specifying a larger size for the image.
CAUTION:
if you are also using a separate /boot partition in your options to vmdebootstrap it may well be the
boot partition which needs to be enlarged rather than the entire image.
It is advisable to change the mirror in the example scripts to a mirror closer to your location,
particularly if you need to do repeated builds. Use the --apt-mirror option to specify the apt mirror to
be used inside the image, after boot.
There are two types of examples for ARM devices available with vmdebootstrap: prebuilt installation
images (like the beaglebone-black) and virtual machine images (cubietruck and wandboard). ARM devices
which do not support hypervisor mode and which also rely on the bootloader being at a specific offset
instead of using a normal partition will not be supportable by vmdebootstrap. Similarly, devices which
support hypervisor will only be supported using virtual machine images, unless the bootloader can be
executed from a normal partition.
If the host device has a limited amount of RAM or simply to use a different TMP directory when preparing
the filesystems, set the TMPDIR or TEMP or TMP environment variables, in line with the underlying support
in the python tempfile module.
DEVELOPING
Testing vmdebootstrap from git
vmdebootstrap uses yarn for the test suite, available in the cmdtest package. YARN is a scenario testing
tool. Scenarios are written in mostly human readable language, however, they are not free form text. For
more information on YARN see the homepage:
$ sudo apt -y install cmdtest
All commits must pass at least the fast tests. All merges into master need to pass a full test. All
additions of new functionality must add fast and build tests --- fast tests for any new options and build
tests which exercise the new functionality. Build tests can add checks for particular support on the
machine running the test and skip if not found or add new environment settings to selectively run some
build tests instead of all.
If no arguments are given, the full test suite will be executed:
$ yarns/run-tests
WARNING:
Do not run the full test suite if your connection to a Debian mirror is limited or metered. Each build
requires a minimum of 2GB free space in tmpfs. A full test takes at least 10 minutes.
When limiting the run to specific tests, each --env option needs to be specified separately:
$ sudo yarns/run-tests --env TESTS=build --env MIRROR=http://mirror/debian
To run a single test, use the --run option to specify the name of the scenario (option can be repeated).
pre-commit
All vmdebootstrap developers need to run the fast tests as a pre-commit hook --- any patches which fail
this test will be rejected:
$ ln -s ../../pre-commit.sh .git/hooks/pre-commit
The pre-commit hook just runs the fast tests which do not require sudo.
Fast tests
The fast checks validate the handling of incompatible option arguments:
$ yarns/run-tests --env TESTS=fast
Fast tests typically take a few seconds to run.
Build tests
The slow / build tests build multiple images and use sudo --- a local mirror is strongly recommended.
$ sudo yarns/run-tests --env TESTS=build --env MIRROR=http://mirror/debian
If MIRROR is not specified, a default mirror of http://httpredir.debian.org/debian/ will be used.
LAVA tests
There is an example lava-submit.py script which can be edited to automatically submit QEMU tests to a
specified LAVA instance. The images themselves will use local file:// URLs and therefore the
lava-dispatcher needs to be installed locally. Configuring LAVA for these tests is a separate topic ---
please ask on the vmdebootstrap mailing list.
AUTHOR
Neil Williams
COPYRIGHT
2018, Neil Williams