Virtualization Comparison

	Proxmox VE	VMware vSphere	Windows Hyper-V	Citrix XenServer
Note: This list is not complete and work in progress. Facts could change from release to release. It provides a very rough overview about some differences and major features.
Guest operating system support	Windows and Linux (KVM) Other operating systems are known to work and are community supported (OpenVZ supports Linux only)	Windows, Linux, UNIX	Modern Windows OS, Linux support is limited	Most Windows OS, Linux support is limited
Open Source	yes	no	no	yes
OpenVZ container (known as OS Virtualization)	yes	no	no	no
Single-view for Mangagement (centralized control)	yes	Yes, but requires dedicated management server (or VM)	Yes, but requires dedicated management server (or VM)	yes
Simple Subscription Structure	Yes, one subscription pricing, all features enabled	no	no	no
High Availability	yes	yes	Requires Microsoft Failover clustering, limited guest OS support	yes
Live VM snapshots: Backup a running VM	yes	yes	limited	yes
Bare metal hypervisor	yes	yes	yes	yes
Virtual machine live migration	yes	yes	yes	yes
Max. RAM and CPU per Host	160 CPU/2 TB Ram	160 CPU/2 TB Ram	64 CPU/1 TB Ram	?

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