.. _acrnctl:

Acrnctl and Acrnd
#################


Description
***********

The ``acrnctl`` tool helps users create, delete, launch, and stop a User
VM (aka UOS).  The tool runs under the Service VM, and User VMs should be based
on ``acrn-dm``. The daemon for acrn-manager is `acrnd`_.

Usage
=====

You can see the available ``acrnctl`` commands by running:

.. code-block:: none

   # acrnctl help
   support:
     list
     start
     stop [--force/-f]
     del
     add
     reset
     blkrescan
   Use acrnctl [cmd] help for details

.. note::
   You must run ``acrnctl`` with root privileges, and make sure the ``acrnd``
   service has been started before running ``acrnctl``.

Here are some usage examples:

Add a VM
========

The ``add`` command lets you add a VM by specifying a
script that will launch a User VM, for example ``launch_uos.sh``:

.. code-block:: none

   # acrnctl add launch_uos.sh -U 1
   vm1-14:59:30 added

If a ``-C`` option is also specified, the VM is launched in a runC
container::

   # acrnctl add launch_uos.sh -C

.. note:: You can download an :acrn_raw:`example launch_uos.sh script
   <misc/config_tools/data/sample_launch_scripts/nuc/launch_uos.sh>`
   that supports the ``-C``  (``run_container`` function) option.

Note that the launch script must only launch one User VM instance.
The VM name is important. ``acrnctl`` searches VMs by their
names so duplicate VM names are not allowed. If the
launch script changes the VM name at launch time, ``acrnctl``
will not recognize it.

Delete VMs
==========

Use the ``delete`` command with a VM name to delete that VM:

.. code-block:: none

   # acrnctl del vm1-14:59:30

List VMs
========

Use the ``list`` command to display VMs and their state:

.. code-block:: none

   # acrnctl list
   vm1-14:59:30            untracked
   vm-ubuntu               stopped
   vm-android              stopped

Start VM
========

If a VM is in a stopped state, you can start it with the ``start`` command. The
``acrnd`` service automatically loads the launch script under
``/usr/share/acrn/conf/add/`` to boot the VM.

.. code-block:: none

   # acrnctl start vm-ubuntu

Stop VM
=======

Use the ``stop`` command to stop one or more running VMs:

.. code-block:: none

   # acrnctl stop vm-ubuntu vm1-14:59:30 vm-android

Use the optional ``-f`` or ``--force`` argument to force the stop operation.
This will trigger an immediate shutdown of the User VM by the ACRN Device Model
and can be useful when the User VM is in a bad state and not shutting down
gracefully by itself.

.. code-block:: none

   # acrnctl stop -f vm-ubuntu

Rescan Block Device
===================

Use the ``blkrescan`` command to trigger a rescan of
virtio-blk device by guest VM, in order to revalidate and
update the backend file.

.. code-block:: none

   # acrnctl blkrescan vmname slot,newfilepath
   vmname:     Name of VM with dummy backend file attached to virtio-blk device.
   slot:       Slot number of the virtio-blk device.
   newfilepath: File path for the backend of virtio-blk device.

   acrnctl blkrescan vm1 6,actual_file.img

.. note:: blkrescan is only supported when VM is launched with
   empty backend file (using **nodisk**) for virtio-blk device.
   Replacing a valid backend file is not supported and will
   result in error.

.. _acrnd:

Acrnd
*****

The ``acrnd`` daemon process provides a way for launching or resuming a User VM
should the User VM shut down, either in a planned manner or unexpectedly. A User
VM can ask ``acrnd`` to set up a timer to make sure the User VM is running, even
if the Service VM is suspended or stopped.

Usage
=====

You can see the available ``acrnd`` commands by running:

.. code-block:: none

   $ acrnd -h
   acrnd - Daemon for ACRN VM Management
   [Usage] acrnd [-t] [-d delay] [-h]
   -t: print messages to stdout
   -d: delay the autostarting of VMs, <0-60> in second (not available in the
       ``RELEASE=1`` build)
   -h: print this message

.. note::
   You must run ``acrnd`` with root privileges.

Normally, ``acrnd`` runs silently (messages are directed to
``/dev/null``).  Use the ``-t`` option to direct messages to ``stdout``,
useful for debugging.

The ``acrnd`` daemon stores pending User VM work to ``/usr/share/acrn/conf/timer_list``
and sets an RTC timer to wake up the Service VM or bring the Service VM back up again.
When ``acrnd`` daemon is restarted, it restores the previously saved timer
list and launches the User VMs at the right time.

A ``systemd`` service file (``acrnd.service``) is installed by default.
You can enable, restart or stop acrnd service using ``systemctl``.

.. code-block:: none

   systemctl enable --now acrnd.service

Build and Install
*****************

Source code for both ``acrnctl`` and ``acrnd`` is in the ``misc/acrn-manager`` folder.
Change to that folder and run:

.. code-block:: none

   $ make
   $ sudo make install
