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adt-virt-qemu - autopkgtest virtualisation server using QEMU


adt-virt-qemu [options] image [ro-image ...]


adt-virt-qemu provides an autopkgtest virtualisation server using QEMU.

Normally adt-virt-qemu will be invoked by adt-run.

You always need to specify at least one QEMU VM image. If your VM needs more disks, you
can specify arbitrarily many additional images which will be added in order.

adt-virt-qemu does not modify the given images, but will instead create a temporary
overlay for the primary image, and add all other images as read-only.

The first image without the overlay is always added as an additional read-only hard drive,
which will be available for tests as /dev/baseimage. This allows tests that require
nested VMs to reuse the same image. Be aware that /dev/baseimage will not be accessible
between calling adt-reboot-prepare and the next boot, thus make sure to stop accessing it


adt-virt-qemu assumes that you have already prepared a suitable Debian based QEMU image
(see BUILDING IMAGES below for how to create them). But you can use any VM which has
python3 or python installed and either

* opens a root shell on ttyS1, or

* has a serial console on ttyS0 where you can log in (getty or similar) with specified
user and password. This will then be used to start a root shell on ttyS1, to reduce
this to the first case and to not assume that ttyS0 stays operational throughout the
whole test.


-u user | --user=user

User name for running tests that don't require root privileges.

If the VM is not already prepared to start a root shell on ttyS1 this will be also
used for logging in on ttyS0. If this is not root, it must be able to run sudo
without a password to become root for that purpose.

-p password | --password=password
Password for above user for logging into the VM on ttyS0. This is necessary if the
VM is not already prepared to start a root shell on ttyS1.

-q command | --qemu-command=command
QEMU command to run. This defaults to the qemu-system-* that matches your system

-o dir | --overlay-dir=dir
Directory where the temporary image overlay for the primary image is created. By
default this will happen in a work directory in /tmp (or $TMPDIR), but you can use
this to e. g. ensure that the overlay is placed on a tmpfs if your /tmp directory
is not on tmpfs. This will greatly increase the speed.

-c num | --cpus=num"
Number of (virtual) CPUs in the VM. Default is 1.

VM RAM size in MiB. Default is 1024, i. e. 1 GiB.

Show boot messages from serial console.

-d | --debug
Enable debugging output.

Pass through arguments to QEMU command; e. g. --qemu-options='-readconfig qemu.cfg'


If you use lots of options or images, you can put parts of, or the whole command line into
a text file, with one line per option. E. g. you can create a file sid-desktop.cfg with
contents like


and then run

adt-run [...] --- adt-virt-qemu @sid-desktop.cfg

The contents of the configuration file will be expanded in-place as if you would have
given its contents on the command line. Please ensure that you don't place spaces between
short options and their values, they would become a part of the argument value.


The behaviour of adt-virt-qemu is as described by the AutomatedTesting virtualisation
regime specification.


adt-run does not run apt-get update at the start of a package build, which can cause a
build failure if you are using a development series template. You will need to run apt-get
update in the template yourself (e. g. using --setup-commands).

If the --qemu-command option has not been specified and no custom CPU type was selected in
--qemu-options, adt-virt-qemu will try to enable nested KVM support by default on x86_64
platforms if the hardware supports this. To fully enable this, one needs to additionally
set some module parameters on the host, by creating a file /etc/modprobe.d/nested_kvm.conf
with the contents

options kvm_intel nested=1
options kvm_amd nested=1

and rebooting or reloading the KVM modules. It is still possible to use QEMU in tests
without this, albeit without hardware acceleration. On Ubuntu systems these module options
are typically already set.


For Debian you can use vmdebootstrap(8) to build a suitable image. E. g. for unstable:

vmdebootstrap --verbose --serial-console --distribution=sid \
--customize=/usr/share/autopkgtest/setup-commands/setup-testbed \
--user=adt/adt --size=10000000000 --grub --image=adt-sid.raw
qemu-img convert -O qcow2 adt-sid.raw adt-sid.img
rm adt-sid.raw

vmdebootstrap can only create a raw format image; it is recommended to convert it to qcow2
as that is much smaller (in the order of 700 MB for qcow2 vs. the 10 GB as specified
above) and also supports additional features such as snapshots or compression. You can run
that command with setting the environment variable ADT_APT_PROXY to a proxy which will be
used by apt in the VM. If you have apt-cacher-ng installed on the host, this will be used
automatically; otherwise you can run e. g.

ADT_APT_PROXY= vmdebootstrap [...]

For Ubuntu, autopkgtest provides adt-buildvm-ubuntu-cloud(1) to build a VM based on the
Ubuntu cloud images. To create an image for the current development series and the i386

adt-buildvm-ubuntu-cloud -v -a i386

This will produce e. g. adt-trusty-i386-cloud.img.


Run the tests of the libpng source package, using an Ubuntu cloud image:

adt-run libpng --- adt-virt-qemu adt-trusty-i386-cloud.img

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