SUSE Linux Enterprise Server DocumentationVirtualization with KVM for IBM System z > Requirements, Limitations, and Support Status > ◀ ▶

Chapter 1. KVM Installation and Requirements

Contents

1.1. Hardware Requirements
1.2. Supported Guest Operating Systems
1.3. The kvm package
1.4. Installing KVM

Abstract

KVM is a full virtualization solution for x86 processors supporting hardware virtualization (Intel VT or AMD-V). It consists of two main components: A set of Kernel modules (kvm.ko, kvm-intel.ko, and kvm-amd.ko) providing the core virtualization infrastructure and processor specific drivers and a userspace program (qemu-kvm) that provides emulation for virtual devices and control mechanisms to manage VM Guests (virtual machines). The term KVM more properly refers to the Kernel level virtualization functionality, but is in practice more commonly used to reference the userspace component.

VM Guests (virtual machines), virtual storage and networks can be managed with libvirt-based and QEMU tools. libvirt is a library that provides an API to manage VM Guests based on different virtualization solutions, among them KVM and Xen. It offers a graphical user interface as well as a command line program. The QEMU tools are KVM/QEMU specific and are only available for the command line.

1.1. Hardware Requirements

Currently, SUSE only supports KVM full virtualization on x86_64 hosts. KVM is designed around hardware virtualization features included in AMD (AMD-V) and Intel (VT-x) CPUs. It supports virtualization features of chipsets, and PCI devices, such as an I/O Memory Mapping Unit (IOMMU) and Single Root I/O Virtualization (SR-IOV)).

You can test whether your CPU supports hardware virtualization with the following command: 

egrep '(vmx|svm)' /proc/cpuinfo

If this command returns no output, your processor either does not support hardware virtualization, or this feature has been disabled in the BIOS.

The following Web site identifies processors which support hardware virtualization: http://ark.intel.com/Products/VirtualizationTechnology (for Intel CPUs), and http://products.amd.com/ (for AMD CPUs).

[Note]

The KVM Kernel modules will not load if the CPU does not support hardware virtualization or if this feature is not enabled in the BIOS.

The general minimum hardware requirements for the VM Host Server are the same as outlined in Section “System Requirements for Operating Linux” (Chapter 2, Installation on x86, AMD64, Intel 64, and Itanium, ↑Deployment Guide). However, additional RAM for each virtualized guest is needed. It should at least be the same amount that is needed for a physical installation. It is also strongly recommended to have at least one processor core or hyper-thread for each running guest.

1.2. Supported Guest Operating Systems

KVM on SUSE Linux Enterprise for IBM System z only supports SLES 11 SP3 as a guest operating system.

The following table lists guest operating systems tested and their support status offered by SUSE. All guest operating systems are supported both fully virtualized and paravirtualized, with the exception of Windows guests, which are only supported fully virtualized and OES and Netware guests, which are supported only paravirtualized. All operating systems except Netware (32-bit only) are supported in both 32 and 64-bit x86 versions.

Para-virtualized drivers (PV drivers) are listed where available.

Para-virtualized drivers for KVM

  • virtio-net: Virtual network driver.

  • virtio-blk: Virtual block device driver for paravirtualized block devices.

  • virtio-balloon: Memory driver for dynamic memory allocation. Allows to dynamically change the amount of memory allocated to a guest.

  • virtio-scsi: Storage interface that supports advanced SCSI hardware.

  • kvm-clock: Clock synchronization driver.

Table 1.1. Supported Guest Operating Systems on KVM with SUSE Linux Enterprise Server

SLES 12

PV drivers:

kvm-clock, virtio-net, virtio-blk, virtio-balloon, virtio-console, virtio-rng, virtio-scsi

Support Status:

Fully supported (L3)

SLES 11 SP3 / SP4

PV drivers:

kvm-clock, virtio-net, virtio-blk, virtio-balloon, virtio-console, virtio-rng, virtio-scsi (SP3 and SP4 only)

Support Status:

Fully supported (L3)

SLES 10 SP4

PV drivers:

kvm-clock, virtio-net, virtio-blk, virtio-balloon, virtio-console

Support Status:

Fully supported (L3)

SLES 9 SP4

PV drivers:

n/a

Support Status:

Fully supported (L3)

Mandatory boot parameters:

32 bit kernel: clock=pmtmr
64 bit kernel: ignore_lost_ticks

SLED 11 SP4

PV drivers:

kvm-clock, virtio-net, virtio-blk, virtio-balloon, virtio-console, virtio-rng

Support Status:

Technology Preview (L2)

RedHat Enterprise Linux 5.11+ / RHEL 6.6+ / RHEL 7.0+

PV drivers:

See http://www.redhat.com/

Support Status:

Best Effort (L2)

Note:

Refer to the RHEL Virtualization guide for more information.

Windows 2003 SP2+ / 2008 SP2+ / 2008 R2 SP1+ / 2012+ / 2012 R2+

PV drivers:

virtio-net, virtio-blk, virtio-balloon; drivers from the Virtual Machine Driver Pack (http://www.suse.com/products/vmdriverpack/) are preferred

Support Status:

Fully supported (L3)

Note:

Host processor must have constant_tsc CPU feature (check with the following command: grep "constant_tsc" /proc/cpuinfo).

Windows XP SP3+ / Vista SP2+ / 7 SP1+ / 8+ / 8.1+

PV drivers:

virtio-net, virtio-blk, virtio-balloon; drivers from the Virtual Machine Driver Pack (http://www.suse.com/products/vmdriverpack/) are preferred

Support Status:

Best effort (L2)

OES 11 SPx

PV drivers:

Support Status:

Fully supported (L3)

Netware 6.5 SP8 (32b only)

PV drivers:

Support Status:

Fully supported (L3)


[Important]

Guest images created under SUSE Linux Enterprise Server 11 SP1 and newer are supported, but guest images created under a previous SUSE Linux Enterprise version are not supported.

1.2.1. Availability of Paravirtualized Drivers

To improve the performance of the guest operating system, paravirtualized drivers are provided when available. Although they are not required, it is strongly recommended to use them. The paravirtualized drivers are available as follows:

SUSE Linux Enterprise Server 11 SP1 / SP2 / SP3

included in Kernel

SUSE Linux Enterprise Server 10 SP4

included in Kernel

SUSE Linux Enterprise Server 9 SP4

not available

RedHat

available in RedHat Enterprise Linux 5.4 and newer

Windows

SUSE has developed virtio based drivers for Windows, which are available in the Virtual Machine Driver Pack (VMDP). See http://www.suse.com/products/vmdriverpack/ for more information.

1.3. The kvm package

The kvm package provides qemu-kvm, the program that performs the I/O emulation for the VM Guest. In addition to the qemu-kvm program, the kvm package also comes with a debug level monitoring utility (kvm_stat), firmware components, key-mapping files, and scripts. The deprecated Windows drivers (win-virtio-drivers.iso) are no longer provided. For more information, see Section A.3.1.1, “Deprecated features”.

Originally, the kvm package also provided the KVM Kernel modules. Now, these modules are included with the Kernel and only userspace components are included in the current kvm package.

Using the libvirt-based tools is the recommended way of managing VM Guests. Interoperability with other virtualization tools has been tested and is an essential part of SUSE's support stance. All tools are provided by packages carrying the tool's name.

  • libvirt: A toolkit that provides management of VM Guests, virtual networks, and storage. libvirt provides an API, a daemon, and a shell (virsh).

  • virt-manager (Virtual Machine Manager): A graphical management tool for VM Guests.

  • vm-install: Define a VM Guest and install its operating system.

  • virt-viewer: An X viewer client for VM Guests which supports TLS/SSL encryption of x509 certificate authentication and SASL authentication.

Support for creating and manipulating file-based virtual disk images is provided by qemu-img. qemu-img is provided by the package virt-utils.

1.4. Installing KVM

KVM is not installed by default. To install KVM and all virtualization tools, proceed as follows:

  1. Start YaST and choose Virtualization+Installing Hypervisor and Tools.

  2. Select KVM and confirm with Accept.

  3. Confirm the list of packages that is to be installed with Install.

  4. Agree to set up a network bridge by clicking Yes. It is recommended using a bridge on a VM Host Server (virtual machine host). If you prefer to manually configure a different network setup, you can safely skip this step by clicking No.

  5. After the setup has been finished, reboot the machine as YaST suggests. Alternatively load the required kernel modules manually and start libvirtd to avoid a reboot: 

    modprobe kvm-intel # on Intel machines only
modprobe kvm-amd   # on AMD machines only
modprobe vhost-net
rclibvirtd start
    modprobe kvm
rclibvirtd start
[Note]The vhost-net Kernel Module

The vhost-net kernel module allows for a more efficient network transport to the guest. It is automatically used by libvirt if loaded, or when using the qemu-kvm command line, by adding ,vhost=on to the networking option.

SUSE Linux Enterprise Server Virtualization with KVM for IBM System z 11 SP4

SUSE Linux Enterprise Server DocumentationVirtualization with KVM for IBM System z > Requirements, Limitations, and Support Status > ◀ ▶