Virtualization Guide

7.1 Host Environments (Hypervisors) #

This section lists the support status of SUSE Linux Enterprise Server 12 SP5 running as a guest on top of various virtualization hosts (Hypervisor).

The following SUSE host environments are supported (Xen + KVM): #

SLES 11 SP4
SLES 12 SP1, SP2, SP3, SP4, SP5
SLES 15 SP0, SP1, SP2

The following 3rd party host environments are supported: #

VMware ESXi 6.5, 6.7
Microsoft Windows 2008 R2 SP1+, 2012+, 2012 R2+, 2016, 2019
Citrix XenServer 7.0, 7.1, 8.0
Oracle VM 3.4

The level of support is as follows: #

Support for SUSE host operating systems is full L3, both for the guest and host.
Support for 3rd party host environments is full L3 for the guest and needs the host vendor cooperation and support for the host.

Note: Support for Third Party Virtualization Hosts

SUSE only provides full L3 support if both the virtualization host and guest are using SUSE products.

If the virtualization host uses third party software, SUSE only guarantees L3 support for the guest. For the host, the cooperation of the vendor is required.

7.2 Guest Environments #

This section lists the support status for various guest operating systems virtualized on top of SUSE Linux Enterprise Server 12 SP5. All guest operating systems are supported both fully-virtualized (“FV” in the following table) and paravirtualized (“PV” in the following table) with two exceptions: Windows, which is only supported fully-virtualized, and NetWare operating systems, which are only supported on Xen paravirtualized. All guest operating systems are supported both in 32-bit and 64-bit flavors, unless stated otherwise (see NetWare).

Important

Microsoft Windows guests can be rebooted by libvirt/virsh only if paravirtualized drivers are installed in the guest. Refer to https://www.suse.com/products/vmdriverpack/ for more details on downloading and installing PV drivers.

The following guest operating systems are fully supported (L3): #

SLES 10 SP4
SLES 11 SP3, SP4
SLES 12 SP0, SP1, SP2, SP3, SP4, SP5
VMware ESXi 2016
SLES 15 SP0, SP1, SP2
OES 11 SP2, 2015, 2015 SP1, 2018, 2018 SP1, 2018 SP2
Netware 6.5 SP8 (32-bit only)
Windows Server 2008 SP2+, 2008 R2 SP1+, 2012+, 2012 R2+, 2016, 2019
Nutanix Acropolis Hypervisor with AOS 5.8

The following guest operating systems are supported as a technology preview (L2, fixes if reasonable): #

SLED 15 SP1

Red Hat and CentOS guest operating systems are fully supported (L3) if the customer has purchased SUSE Liberty Linux. #

Refer to the SUSE Liberty Linux documentation at https://documentation.suse.com/liberty for the list of available combinations and supported releases. In other cases, they are supported on a limited basis (L2, fixes if reasonable).

The following guest operating systems are supported on a commercially reasonable basis (L2, fixes if reasonable): #

Windows 8+, 8.1+, 10+

7.2.1 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 12 / 12 SP1 / 12 SP2: Included in kernel
SUSE Linux Enterprise Server 11 / 11 SP1 / 11 SP2 / 11 SP3 / 11 SP4: Included in kernel
SUSE Linux Enterprise Server 10 SP4: Included in kernel
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). For more information, see https://www.suse.com/products/vmdriverpack/.

7.3 KVM Hardware Requirements #

Currently, SUSE supports KVM full virtualization on AMD64/Intel 64 and Arm AArch64 hosts, and on IBM Z.

On the AMD64/Intel 64 architecture, 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:
```
tux > 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 or firmware.
The following Web sites identify AMD64/Intel 64 processors that support hardware virtualization: http://ark.intel.com/Products/VirtualizationTechnology (for Intel CPUs), and http://products.amd.com/ (for AMD CPUs).
On the Arm AArch64 architecture, virtualization support was initially added to ARMv7-A processors starting with Cortex-A15 and including Cortex-A7 and Cortex-A17. ARMv8-A processors include support for virtualization.

Note: KVM Kernel Modules Not Loading

The KVM kernel modules only load if the CPU hardware virtualization features are available.

The general minimum hardware requirements for the VM Host Server are the same as for a physical machine. 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.

7.4 Feature Support #

7.4.1 Host (Dom0) #

Table 7.1: Feature Support—Host (Dom0) #

Features	Xen
Network and block device hotplugging	Yes
Physical CPU hotplugging	No
Virtual CPU hotplugging	Yes
Virtual CPU pinning	Yes
Virtual CPU capping	Yes
Intel* VT-x2: FlexPriority, FlexMigrate (migration constraints apply to dissimilar CPU architectures)	Yes
Intel* VT-d2 (DMA remapping with interrupt filtering and queued invalidation)	Yes
AMD* IOMMU (I/O page table with guest-to-host physical address translation)	Yes

Note: Adding or Removing Physical CPUs at Runtime Is Not Supported

The addition or removal of physical CPUs at runtime is not supported. However, virtual CPUs can be added or removed for each VM Guest.

7.4.2 Paravirtualized Guest #

Table 7.2: Feature Support—Paravirtualized Guest #

Features	Xen
Virtual network and virtual block device hotplugging	Yes
Virtual CPU hotplugging	Yes
Virtual CPU over-commitment	Yes
Dynamic virtual memory resize	Yes
VM save and restore	Yes
VM live migration	Yes, between like virtual host systems with similar resources
Advanced debugging with GDBC	Yes
Dom0 metrics visible to VM	Yes
Memory ballooning	Yes
PCI pass-through	Yes (Netware guests are excluded)

For live migration, both source and target system architectures need to match; that is, the processors (AMD* or Intel*) must be the same. Unless CPU ID masking is used, such as with Intel FlexMigration, the target should feature the same processor revision or a more recent processor revision than the source. If VMs are moved among different systems, the same rules apply for each move. To avoid failing optimized code at runtime or application start-up, source and target CPUs need to expose the same processor extensions. Xen exposes the physical CPU extensions to the VMs transparently. To summarize, guests can be 32-bit or 64-bit, but the VHS must be identical.

Note: Intel FlexMigration

For machines that support Intel FlexMigration, CPU-ID masking and faulting allow more flexibility in cross-CPU migration.

7.4.3 Fully Virtualized Guest #

Table 7.3: Feature Support—Fully Virtualized Guest #

Features	Xen	KVM
Virtual network and virtual block device hotplugging	Yes	Yes
Virtual CPU hotplugging	No	No
Virtual CPU over-commitment	Yes	Yes
Dynamic virtual memory resize	Yes	Yes
VM save and restore	Yes	Yes
VM Live Migration	Yes between like virtual host systems with similar resources (that is, from 32-bit to 32-bit, 64-bit to 64-bit)	Yes
VM snapshot	Yes	Yes
Advanced debugging with GDBC	Yes	Yes
Dom0 metrics visible to VM	Yes	Yes
PCI pass-through	Yes	Yes

Note: Windows Guest

Hotplugging of virtual network and virtual block devices, and resizing, shrinking, and restoring dynamic virtual memory are supported in Xen and KVM only if PV drivers are being used (VMDP).

For KVM, a detailed description of supported limits, features, recommended settings and scenarios, and other useful information is maintained in kvm-supported.txt. This file is part of the KVM package and can be found in /usr/share/doc/packages/kvm.