Virtualization technology has played an important role in shaping up the web hosting and data center industry to its present state. The purpose of this article is to discuss server virtualization and different leading software for virtualization along with stacking up their features at a single place.
What is server virtualization?
Creating a virtual or isolated form of an IT environment is called virtualization. Typically, only a single application or operating system can be run by servers, which leads to inefficient resource utilization. When the servers are virtualized, a single server can run multiple applications and operating systems. It increases overall efficiency, as well as cost-effectiveness. The server virtualization software is generally referred to as a hypervisor.
Best server virtualization software in 2019
Citrix XenServer, Microsoft Hyper-V, Red Hat KVM, and VMware vSphere are the biggest players in the server virtualization market. Often, enterprises can’t decide which hypervisor will best suit their business.
A comparison between major server virtualization software on the basis of features and hardware requirements will make it easier for IT decision makers and end users to select the best hypervisor for them.
Comparison: Hyper-V vs KVM vs vSphere vs XenServer
Note: The software have been placed in the alphabetical order of their names.
Launched in 2008, Microsoft Hyper-V helps in expanding or establishing a private cloud environment. It promotes effective hardware utilization, improves business continuity, as well as makes development and test more efficient.
Features of Microsoft Hyper-V for Windows Server 2019:
- Persistent memory support.
- Shielded VM updates.
- Simple Two-Node clusters.
- ReFS Deduplication.
- Storage Spaces Direct improvements.
- Windows Admin Center.
- Encrypted subnets.
For further details about Hyper-V, you can read this PDF.
KVM (Kernel-based Virtual Machine), a part of Red Hat Virtualization Suite, is a complete virtualization infrastructure solution. KVM turns Linux kernel into a hypervisor. It was merged into the Linux kernel mainline in kernel version 2.6.20.
Features of Red Hat KVM:
- Container support
- Overcommit resources
- Disk I/O throttling
- Hot plug of virtual resources
- Low-cost virtualization solution
- Red Hat Enterprise Virtualization programming & API
- Live Migration & Storage Migration
- Assign any PCI device to virtual machines
- Red Hat Satellite integration
- Disaster Recovery support
Read this feature guide about KVM for details.
vSphere, the virtualization platform of VMware, is a set of products that not only includes virtualization, but also management and interface layers.
It provides a number of key components including infrastructure services (vCompute, vStorage, and vNetwork), application services, vCenter Server, vSphere Client, etc.
Features of VMware vSphere:
- vCenter Server: A centralized management tool used to configure, provision and manage virtual IT environments.
- vSphere Client: vSphere 6.7 has the final version of Flash-based vSphere Web Client. Newer workflows in the updated vSphere Client release includes vSphere Update Manager, Content library, vSAN, Storage policies, Host profiles, VMware vSphere Distributed Switch™ topology diagram and Licensing.
- vSphere SDKs: Provides interfaces for third-party solutions to access vSphere.
- VM File System: Cluster file system for VMs.
- Virtual SMP: Enables a single VM to use multiple physical processors at a time.
- vMotion: Enables live migration with transaction integrity.
- Storage vMotion: Enables VM file migration from one place to other without service interruption.
- High Availability: If one server fails, VM is shifted to other server with spare capacity to enable business continuity.
- Distributed Resource Scheduler (DRS): Assigns and balances compute automatically across hardware resources available for VMs.
- Fault Tolerance: Generates copy of primary VM to ensure its continuous availability.
- Distributed Switch (VDS): Spans multiple ESXi hosts and enables considerable reduction of network maintenance activities.
Read this PDF for more information about vSphere.
Based on Xen Project Hypervisor, XenServer is an open sourced bare-metal virtualization platform. It consists of enterprise-grade features that help enterprises to easily handle workloads, combined OS, and networking configurations.
XenServer provides improved virtualized graphics with NIVIDA and Intel and allows execution of multiple computer operating systems on same computer hardware.
Features of Citrix XenServer:
- Site Recovery
- Host Failure Protection
- Multi-server management
- Dynamic Memory Control
- Active Directory Integration
- Role Based Administration and Control (RBAC)
- Mixed Resource Pools with CPU Masking
- Distributed Virtual Switch Controller
- In Memory read caching
- Live VM migration & Storage XenMotion
For details, you can read this PDF.
vSphere vs XenServer vs Hyper-V vs KVM
|Feature||Windows Hyper-V 2019||vSphere 6.7||XenServer 7.6||KVM|
|RAM/VM||12 TB for generation 2;||6 TB||1.5TB||6 TB|
|1 TB for generation 1|
|CPUs/VM||240 for generation 2;||128||32||240|
|64 for generation 1;|
|VM Disk||64 TB for VHDX format;||62TB||2TB||10TB|
|2040 GB for VHD format|
|VM Live Migration||Yes||Yes||Yes||Yes|
|VM Replication supports||Yes||Yes||Yes||Yes|
|Disk I/O Throttling||Yes||Yes||Yes||Yes|
|Hot plug of virtual resources||Yes||Yes||Yes||Yes|
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Disclaimer: This article has been updated on 11th January 2019 with information available on vendor websites and resources available in the public domain. The purpose of this article is to provide information about hypervisors of different vendors for general informational purpose only. Vendors may change their product features from time to time. Though we make best endeavors to ensure that the information is accurate and up to date, we do not guarantee its 100% accuracy or timeliness.