Proxmox VE in brief

With Proxmox VE, Proxmox Server Solutions GmbH (https://www.proxmox.com/en/about) provides us with an enterprise-ready, open source type 2 Hypervisor. Later, you'll find some of the features that make Proxmox VE such a strong enterprise candidate.

• The license for Proxmox VE is very deliberately the GNU Affero General Public License (V3) (https://www.gnu.org/licenses/agpl-3.0.html). From among the many free and open source compatible licenses available, this is a significant choice because it is "specifically designed to ensure cooperation with the community in the case of network server software."
• PVE is primarily administered from an integrated web interface, from the command line locally, or via SSH. Consequently, there is no need for a separate management server and the associated expenditure. In this way, Proxmox VE significantly contrasts with alternative enterprise virtualization solutions by vendors such as VMware.
• Proxmox VE instances/nodes can be incorporated into PVE clusters, and centrally administered from a unified web interface.
• Proxmox VE provides for live migration—the movement of a virtual machine or container from one cluster node to another without any disruption of services. This is a rather unique feature of PVE and not common in competing products.

Features	Proxmox VE	VMware vSphere
Hardware requirements	Flexible	Strict compliance with HCL
Integrated management interface	Web- and shell-based (browser and SSH)	No. Requires dedicated management server at additional cost
Simple subscription structure	Yes; based on number of premium support tickets per year and CPU socket count	No
High availability	Yes	Yes
VM live migration	Yes	Yes
Supports containers	Yes	No
Virtual machine OS support	Windows and Linux	Windows, Linux, and Unix
Community support	Yes	No
Live VM snapshots	Yes	Yes

Contrasting Proxmox VE and VMware vSphere features

Note

For a complete catalog of features, see the Proxmox VE datasheet at https://www.proxmox.com/images/download/pve/docs/Proxmox-VE-Datasheet.pdf.

Like its competitors, PVE is a hypervisor: a typical hypervisor is software that creates, runs, configures, and manages virtual machines based on an administrator or engineer's choices.

PVE is known as a type 2 hypervisor because the virtualization layer is built upon an operating system.

As a type 2 hypervisor, Proxmox VE is built on the Debian project. Debian is a GNU/Linux distribution renowned for its reliability, commitment to security, and its thriving and dedicated community of contributing developers.

A type 2 hypervisor, such as PVE, runs directly over the operating system. In Proxmox VE's case, the operating system is Debian; since the release of PVE 4.0, the underlying operating system has been Debian "Jessie."

By contrast, a Type I Hypervisor (such as VMware's ESXi) runs directly on bare metal without the mediation of an operating system. It has no additional function beyond managing virtualization and the physical hardware.

A type I hypervisor runs directly on hardware, without the mediation of an operating system.

Note

Debian-based GNU/Linux distributions are arguably the most popular GNU/Linux distributions for the desktop.

One characteristic that distinguishes Debian from competing distributions is its release policy: Debian releases only when its development community can ensure its stability, security, and usability.

Debian does not distinguish between long-term support releases and regular releases as do some other distributions.

Instead, all Debian releases receive strong support and critical updates throughout the first year following the next release. (Since 2007, a major release of Debian has been made about every two years. Debian 8, Jessie, was released just about on schedule in 2015.

Proxmox VE's reliance on Debian is thus a testament to its commitment to these values: stability, security, and usability during scheduled releases that favor cutting-edge features.

PVE provides its virtualization functionality through three open technologies managed through a unified web-based interface:

• LXC
• KVM
• QEMU

To understand how this foundation serves Proxmox VE, we must first be able to clearly understand the relationship between virtualization (or, specifically, hardware virtualization) and containerization (OS virtualization). As we proceed, their respective use cases should become clear.