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:

# 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 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:

# 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 example launch_uos.sh script 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:

# acrnctl del vm1-14:59:30

List VMs

Use the list command to display VMs and their state:

# 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:

# acrnctl start vm-ubuntu

Stop VM

Use the stop command to stop one or more running VM:

# 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.

# 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.

# 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

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:

$ 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.

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:

$ make
$ sudo make install