This article approaches the technical overview and comparison of best server virtualization software, from an application and performance point of view.
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 hypervisor.
Best server virtualization software in 2018
Microsoft Hyper-V, VMware vSphere, Citrix XenServer, and Red Hat KVM, are the biggest players in the server virtualization market. Often, enterprises can’t decide which hypervisor will best suit their business.
The detailed comparison between major server virtualization software, on the basis of features, key factors including licensing costs, virtual machine density, training costs, hardware requirements, etc. will make the things easier for IT decision makers and end users to select the best hypervisor for them.
Comparison: Microsoft Hyper-V vs VMware vSphere vs Citrix XenServer vs Red Hat KVM
1. Microsoft Hyper-V
Launched in 2008, 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:
- Nested virtualization
- Discrete device assignment
- Cloud backup
- Supports containerization
- Quality of service (QoS) for software-defined networks
- Supports resizing of virtual hard disks, memory, CPU while the VM is running
- Live migration & Storage Migration
- Replication (host to host replica for DR purpose)
- Comprehensive security through Windows Active Directory
- Storage Quality of Service (QoS)
- Windows PowerShell Direct (new)
For further details about Hyper-V, you can read this PDF.
2. VMware vSphere
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: Enables remote connection to vCenter Server or ESXi from a Windows PC.
- 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.
3. Citrix XenServer
Based on Xen Project Hypervisor, XenServer is an open sourced bare-metal virtualization platform. It consists enterprise-grade features that helps 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.
4. Red Hat KVM
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 vs XenServer vs Hyper-V vs KVM
|Feature||Hyper-V 2016||vSphere 6.5||XenServer||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|
For any query related to hypervisors, please comment below!