clear-linux-documentation/source/get-started/virtual-machine-install/kvm.rst

.. _kvm:

|CL-ATTR| on KVM
################

This page explains how to run |CL-ATTR| in a virtualized environment using
:abbr:`KVM (Kernel-based Virtual Machine)`.

.. contents::
   :local:
   :depth: 1

Install QEMU-KVM
****************

#. Enable the `Intel® Virtualization Technology`_ (Intel® VT) and the
   `Intel® Virtualization Technology for Directed I/O`_ (Intel® VT-d) in the
   host machine’s BIOS.

#. Log in and open a terminal emulator.

#. Install `QEMU*-KVM` on the host machine. Below are some examples using
   different distros:

   ====================    =========================================
   Host OS                 Installation command
   ====================    =========================================
   |CL|                    :command:`sudo swupd bundle-add kvm-host`
   --------------------    -----------------------------------------
   Ubuntu\* and Mint\*     :command:`sudo apt-get install qemu-kvm`
   --------------------    -----------------------------------------
   Fedora                  :command:`dnf install qemu-kvm`
   ====================    =========================================

Download and launch the virtual machine image
*********************************************

#. Download the latest pre-built |CL| KVM image file from
   the `image <https://cdn.download.clearlinux.org/image/>`_ directory. Look for
   ``clear-<version>-kvm.img.xz``.  You can also use this command:

   .. code-block:: bash

      curl -o clear.img.xz https://cdn.download.clearlinux.org/image/$(curl https://cdn.download.clearlinux.org/image/latest-images.json | grep -o 'clear-[0-9]*-kvm.img.xz' | head -1)

#. Uncompress the downloaded image:

   .. code-block:: bash

      xz -dv clear.img.xz

#. Download the 3 OVMF files (`OVMF.fd`, `OVMF_CODE.fd`, `OVMF_VARS.fd`) that
   provides UEFI  support for virtual machines.

   .. code-block:: bash

      curl -O https://cdn.download.clearlinux.org/image/OVMF.fd
      curl -O https://cdn.download.clearlinux.org/image/OVMF_CODE.fd
      curl -O https://cdn.download.clearlinux.org/image/OVMF_VARS.fd

   .. note::

      The default OVMF files from |CL| may not work for some non-|CL| distro
      version(s). You may get an `ASSERT` in the `debug.log` file when
      starting the VM. If you encounter this, use the distro-specific OVMF
      files instead.


#. Download the `start_qemu.sh`_ script from the
   `image <https://cdn.download.clearlinux.org/image/>`_ directory.  This script
   will launch the |CL| VM and provide console interaction within the same
   terminal emulator window.

   .. code-block:: bash

      curl -O https://cdn.download.clearlinux.org/image/start_qemu.sh

#. Start the |CL| KVM virtual machine:

   .. code-block:: bash

      sudo bash ./start_qemu.sh clear.img

#. Log in as ``root`` user and set a new password.

Optional: Enable SSH access
***************************

To interact with the |CL| VM remotely through SSH instead of the console it
was launched from, follow these steps.

#. Enable and configure SSH in the |CL| VM to allow root login as described in
   :ref:`openssh-server`.


#. SSH into the |CL| VM using the port `10022`. This port number is set in
   :file:`start_qemu.sh` and passed through to the SSH service running on port
   22

   .. code-block:: bash

      ssh -p 10022 root@<ip-addr-of-kvm-host>


Optional: Install a graphical user interface (GUI)
**************************************************

To add :abbr:`GDM (GNOME Display Manager)` to the |CL| VM, follow these steps:

#. Shutdown the active |CL| VM.

   .. code-block:: bash

      poweroff

#. Install the Spice viewer on the localhost or remote system. Below are some
   examples using different distros:

   ====================    =========================================
   Host OS                 Installation command
   ====================    =========================================
   |CL|                    :command:`sudo swupd bundle-add virt-viewer`
   --------------------    -----------------------------------------
   Ubuntu\* and Mint\*     :command:`sudo apt-get install virt-viewer`
   --------------------    -----------------------------------------
   Fedora                  :command:`dnf install virt-viewer`
   ====================    =========================================


#. Modify the :file:`start_qemu.sh` script to increase memory (`-m`), add
   graphics driver (`-vga`), and add Spice (`-spice`, `-usb`, and
   `-device`) support.

   .. code-block:: console
      :emphasize-lines: 5-10

      qemu-system-x86_64 \
          -enable-kvm \
          ${UEFI_BIOS} \
          -smp sockets=1,cpus=4,cores=2 -cpu host \
          -m 4096 \
          -vga qxl \
          -nographic \
          -spice port=5924,disable-ticketing \
          -usb \
          -device usb-tablet,bus=usb-bus.0 \
          -drive file="$IMAGE",if=virtio,aio=threads,format=raw \
          -netdev user,id=mynet0,hostfwd=tcp::${VMN}0022-:22,hostfwd=tcp::${VMN}2375-:2375 \
          -device virtio-net-pci,netdev=mynet0 \
          -debugcon file:debug.log -global isa-debugcon.iobase=0x402 $@

#. Due to changes in the :file:`start_qemu.sh` script from the previous step,
   having previously used OVMF files will result in the VM not booting
   properly and you returning to the UEFI shell. The easiest way to avoid this
   is to delete the 3 OVMF files and reobtain originals before relaunching the
   VM:

   .. code-block:: bash

      rm -v OVMF*.fd
      curl -O https://cdn.download.clearlinux.org/image/OVMF.fd
      curl -O https://cdn.download.clearlinux.org/image/OVMF_CODE.fd
      curl -O https://cdn.download.clearlinux.org/image/OVMF_VARS.fd

#. Increase the size of the VM by 10GB to accommodate the GDM installation:

   .. code-block:: bash

      qemu-img resize -f raw clear-<version>-kvm.img +10G

#. Relaunch the |CL| VM:

   .. code-block:: bash

      sudo ./start_qemu.sh clear.img

#. Determine the IP address of the host on which you will launch the VM.
   Substitute <ip-addr-of-kvm-host> in the next step with this information.

   .. code-block:: bash

      ip a
      

#. From the local host or remote system, open a new terminal emulator window
   and connect into the |CL| VM using the Spice viewer:

   .. code-block:: bash

      remote-viewer spice://<ip-address-of-kvm-host>:5924

#. Log in as `root` user into the |CL| VM.

#. Follow these steps from :ref:`increase-virtual-disk-size` to resize the
   partition of the virtual disk of the VM.

#. Add GDM to the |CL| VM:

   .. code-block:: bash

      swupd bundle-add desktop-autostart

#. Reboot the |CL| VM to start GDM:

   .. code-block:: bash

      reboot

#. Go through the GDM out-of-box experience (OOBE).

#. The default aspect ratio of the GDM GUI for the |CL| VM is 4:3. To change
   it, use GDM's `Devices > Displays` setting tool (located at the top-right
   corner).


*Intel and the Intel logo are trademarks of Intel Corporation or its subsidiaries.*

.. _Intel® Virtualization Technology: https://www.intel.com/content/www/us/en/virtualization/virtualization-technology/intel-virtualization-technology.html
.. _Intel® Virtualization Technology for Directed I/O: https://software.intel.com/en-us/articles/intel-virtualization-technology-for-directed-io-vt-d-enhancing-intel-platforms-for-efficient-virtualization-of-io-devices
.. _start_qemu.sh: https://cdn.download.clearlinux.org/image/start_qemu.sh