Applies to SUSE Linux Enterprise Server 15 SP2

5 Installation of Virtualization Components #

Depending on the scope of the installation, none of the virtualization tools may be installed on your system. They will be automatically installed when configuring the hypervisor with the YaST module Virtualization › Install Hypervisor and Tools. In case this module is not available in YaST, install the package yast2-vm.

5.1 Installing KVM #

To install KVM and KVM tools, proceed as follows:

Verify that the yast2-vm package is installed. This package is YaST's configuration tool that simplifies the installation of virtualization hypervisors.
Start YaST and choose Virtualization › Install Hypervisor and Tools.
Select KVM server for a minimal installation of QEMU tools. Select KVM tools if a libvirt-based management stack is also desired. Confirm with Accept.
To enable normal networking for the VM Guest, using a network bridge is recommended. YaST offers to automatically configure a bridge on the VM Host Server. Agree to do so by choosing Yes, otherwise choose No.
After the setup has been finished, you can start setting up VM Guests. Rebooting the VM Host Server is not required.

5.2 Installing Xen #

To install Xen and Xen tools, proceed as follows:

Start YaST and choose Virtualization › Install Hypervisor and Tools.
Select Xen server for a minimal installation of Xen tools. Select Xen tools if a libvirt-based management stack is also desired. Confirm with Accept.
To enable normal networking for the VM Guest, using a network bridge is recommended. YaST offers to automatically configure a bridge on the VM Host Server. Agree to do so by choosing Yes, otherwise choose No.
After the setup has been finished, you need to reboot the machine with the Xen kernel.
Tip: Default Boot Kernel
If everything works as expected, change the default boot kernel with YaST and make the Xen-enabled kernel the default. For more information about changing the default kernel, see Section 14.3, “Konfigurieren des Bootloaders mit YaST”.

5.3 Installing Containers #

To install containers, proceed as follows:

Start YaST and choose Virtualization › Install Hypervisor and Tools.
Select libvirt lxc daemon and confirm with Accept.

5.4 Patterns #

It is possible using Zypper and patterns to install virtualization packages. Run the command zypper in -t pattern PATTERN. Available patterns are:

KVM

kvm_server: sets up the KVM VM Host Server with QEMU tools for management
kvm_tools: installs the libvirt tools for managing and monitoring VM Guests

Xen

xen_server: sets up the Xen VM Host Server with Xen tools for management
xen_tools: installs the libvirt tools for managing and monitoring VM Guests

Containers

There is no pattern for containers; install the libvirt-daemon-lxc package.

5.5 Installing UEFI Support #

Note

KVM guests support secure boot by using the OVMF firmware. Xen HVM guests support booting from the OVMF firmware as well, but they do not support secure boot.

UEFI support is provided by OVMF (Open Virtual Machine Firmware). To enable UEFI boot, first install the qemu-ovmf-x86_64 or qemu-uefi-aarch64 package depending on the architecture of the guest.

The firmware used by virtual machines is auto-selected. The auto-selection is based on the *.json files in the qemu-ovmf-ARCH package. The libvirt QEMU driver parses those files when loading so it knows the capabilities of the various types of firmware. Then when the user selects the type of firmware and any desired features (for example, support for secure boot), libvirt will be able to find a firmware that satisfies the user's requirements.

For example, to specify EFI with secure boot, use the following configuration:

<os firmware='efi'>
 <loader secure='yes'/>
</os>

The qemu-ovmf-ARCH packages contain the following files:

# rpm -ql qemu-ovmf-x86_64
[...]
/usr/share/qemu/ovmf-x86_64-ms-code.bin
/usr/share/qemu/ovmf-x86_64-ms-vars.bin
/usr/ddshare/qemu/ovmf-x86_64-ms.bin
/usr/share/qemu/ovmf-x86_64-suse-code.bin
/usr/share/qemu/ovmf-x86_64-suse-vars.bin
/usr/share/qemu/ovmf-x86_64-suse.bin
[...]

The *-code.bin files are the UEFI firmware files. The *-vars.bin files are corresponding variable store images that can be used as a template for a per-VM non-volatile store. libvirt copies the specified vars template to a per-VM path under /var/lib/libvirt/qemu/nvram/ when first creating the VM. Files without code or vars in the name can be used as a single UEFI image. They are not as useful since no UEFI variables persist across power cycles of the VM.

The *-ms*.bin files contain Microsoft keys as found on real hardware. Therefore, they are configured as the default in libvirt. Likewise, the *-suse*.bin files contain preinstalled SUSE keys. There is also a set of files with no preinstalled keys.

For details, see Using UEFI and Secure Boot and http://www.linux-kvm.org/downloads/lersek/ovmf-whitepaper-c770f8c.txt.

5.6 Enable Support for Nested Virtualization in KVM #

Important: Technology Preview

KVM's nested virtualization is still a technology preview. It is provided for testing purposes and is not supported.

Nested guests are KVM guests run in a KVM guest. When describing nested guests, we will use the following virtualization layers:

L0: A bare metal host running KVM.
L1: A virtual machine running on L0. Because it can run another KVM, it is called a guest hypervisor.
L2: A virtual machine running on L1. It is called a nested guest.

Nested virtualization has many advantages. You can benefit from it in the following scenarios:

Manage your own virtual machines directly with your hypervisor of choice in cloud environments.
Enable the live migration of hypervisors and their guest virtual machines as a single entity.
Use it for software development and testing.

To enable nesting temporarily, remove the module and reload it with the nested KVM module parameter:

For Intel CPUs, run:

> sudo modprobe -r kvm_intel && modprobe kvm_intel nested=1

For AMD CPUs, run:

> sudo modprobe -r kvm_amd && modprobe kvm_amd nested=1

To enable nesting permanently, enable the nested KVM module parameter in the /etc/modprobe.d/kvm_*.conf file, depending on your CPU:

For Intel CPUs, edit /etc/modprobe.d/kvm_intel.conf and add the following line:
```
options kvm_intel nested=1
```
For AMD CPUs, edit /etc/modprobe.d/kvm_amd.conf and add the following line:
```
options kvm_amd nested=1
```

When your L0 host is capable of nesting, you will be able to start an L1 guest in one of the following ways:

Use the -cpu host QEMU command line option.
Add the vmx (for Intel CPUs) or the svm (for AMD CPUs) CPU feature to the -cpu QEMU command line option, which enables virtualization for the virtual CPU.

5.6.1 VMware ESX as a guest hypervisor #

If you use VMware ESX as a guest hypervisor on top of a KVM bare metal hypervisor, you may experience unstable network communication. This problem occurs especially between nested KVM guests and the KVM bare metal hypervisor or external network. The following default CPU configuration of the nested KVM guest is causing the problem:

<cpu mode='host-model' check='partial'/>

To fix it, modify the CPU configuration as follow:

[...]
<cpu mode='host-passthrough' check='none'>
 <cache mode='passthrough'/>
</cpu>
[...]