====== Virtualisierung (KVM) ======

===== Programme =====
^ [[admin:linux:virt-manager|virt-manager]] | GUI zum Verwalten von KVM-basierten VMs |
^ ''virsh'' | CLI-Manager für KVM-VMs |
^ gnome-boxes | Noch eine GUI für KVM-VMs, aber einfacher zu bedienen |

===== virt-install =====

''virt-install --prompt'' führt einen durch die Erstellung einer VM.

==== Windows ====

<code>
virt-install \
   --name=guest-name \
   --os-type=windows \
   --network network=default \
   --disk path=path-to-disk,size=disk-size \
   --cdrom=path-to-install-disk \
   --graphics spice --ram=1024
</code>

> All image files are stored in /var/lib/libvirt/images/ by default. Other directory locations for file-based images are possible, but may require SELinux configuration.

[Quelle: [[https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Virtualization_Host_Configuration_and_Guest_Installation_Guide/sect-Virtualization_Host_Configuration_and_Guest_Installation_Guide-Windows_Installations-Installing_Windows_XP_as_a_fully_virtualized_guest.html|Red Hat – using virt-install to create a Windows guest]]]

===== Netzwerk =====

==== Bridge zum internen Netzwerk ====

<file - /etc/network/interfaces># The primary network interface
auto eno1
  iface eno1 inet manual

auto br0
  iface br0 inet dhcp
  bridge_ports eno1</file>

anschließend: ''systemctl restart networking''

===== Windows-Gast =====

Performance mit virtio-Treibern ist weitaus höher, siehe auch:

  * [[https://forum.level1techs.com/t/how-fast-is-kvm-host-vs-virtual-machine-performance/110192|How Fast is KVM?]]
  * [[https://docs.fedoraproject.org/quick-docs/en-US/creating-windows-virtual-machines-using-virtio-drivers.html|Creating Windows VMs with virtio drivers (Fedora Quick Docs)]]

===== Fehlerbehebung =====

==== Failed to initialize a valid firewall backend ====

Install and start ''ebtables'' and ''dnsmasq''. Restart ''libvirtd'' afterwards.

==== INACCESSIBLE_BOOT_DEVICE after virtio ====

If this error occurs after you set the boot drive to virtio, you should do the following:

  - ''bcdedit /set "{current}" safeboot minimal''
  - change the boot device type to virtio.
  - boot the VM. It will enter in safe mode.
    - all boot-start drivers will be enabled and loaded, including the virtio driver. Since there is now a miniport installed to use it, the kernel will make it part of the drivers that are to be loaded on boot and not disable it again.
  - in the booted VM reset the bcdedit settings to allow the machine to boot into the normal mode:\\ ''bcdedit /deletevalue "{current}" safeboot''

=== option 2 ===

If that doesn't work, add a virtio device, boot, install the virtio drivers, shutdown, remove the virtio disk, change IDE boot disk to virtio.