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Virtualization has become the norm in software and operating system testing. It is used by everyone from enthusiasts to developers.server virtualizationallows multiple operating systems to run on the same physical resources. This reduces the numberphysical dedicated serversnecessary.
A hypervisor creates a virtualization layer that separates the guest computer and the underlying operating system. The hypervisor emulates resources so guest operating systems assume they are using all physical resources. You cannot see the host OS or other VMs running on the same resources.
There aretwo types of hypervisors:
- Typ 1Bare-Metal-Hypervisor.installed on the physical server.
- Type 2 (hosted) hypervisors installed on the host operating system.
While Type 1 is more suitable for large production environments, hosted hypervisors are used for virtual machines running on personal computers. The most common type 2 hypervisor software are VirtualBox and VMware.
In this tutorial, you will learn more about the difference between VirtualBox and VMware.

What is VirtualBox?
VirtualBox belongs to Oraclex86IAMD64/Intel64 Virtualization Software. It is a free, open-source virtualization product distributed under the nameGNU General Public License (GPL)Version 2.
The software allows you to run virtual machines on the host operating system. In addition, you can establish a managed connection between virtual machines and even a host if required.
You can run VirtualBox on Linux, Windows, Mac OS, and Oracle Solaris.
In 2010, Oracle introduced the so-calledVirtualBox Extension Pack, a supplemental closed-source package with additional features. It included features like USB2/USB3 and RDP support.
Note:Another way to create isolated virtual environments is by using Docker containers. ViewComparison of virtual machines with containersin direct comparison.
What is VMware?
VMware offers many virtualization products.VMware Workstation Playeris freex64Virtualization software for non-commercial use. The company emphasizes that the free version is intended for students and teachers. If you want to use the player for commercial purposes, you need to pay for the Workstation Player commercial license.
It is used to manage and create virtual machines, but works best when running a single virtual machine. You can install free virtualization software if you have a Linux or Windows host.
If you need virtualization software with more features and bigger projects, you can check out Workstation Pro.
Virtualbox vs VMware: comparison table
Comparison | VirtualBox | VMware |
---|---|---|
software virtualization | So | NO |
hardware virtualization | So | So |
host operating systems | Linux, Windows, Solaris, macOS, FreeBSD | Linux, Windows + macOS (erfordert VMware Fusion) |
guest operating systems | Linux, Windows, Solaris, macOS, FreeBSD | Linux, Windows, Solaris, FreeBSD + macOS (z VMware Fusion) |
user interface | Graphical User Interface (GLI) and Command Line Interface (CLI) | Graphical User Interface (GLI) and Command Line Interface (CLI) |
snapshots | So | Snapshots are only supported in paid virtualization products, not in VMware Workstation Player |
Format of the virtual disk | VDI, VMDK, VHD, HDD | weapons of mass destruction |
Virtual disk allocation type | Default: hard disks; Dynamically allocated: dynamically allocated disks; | Preallocated: shared drives; Dynamically allocated: sparsely allocated disks; |
Virtual Network Models | Not Connected, NAT, Network NAT, Bridge Adapter, Internal Network, Host Only Adapter, Generic (UDP, VDE) | NAT, Bridged, Host-only + Virtual Network Editor (auf VMware Workstation und Fusion Pro) |
Support for USB devices | USB 2.0/3.0 support requires expansion pack (free) | USB device support out of the box |
Graphic 3D | Up to OpenGL 3.0 and Direct3D 9; Up to 128MB video memory; 3D acceleration manually enabled | Up to OpenGL 3.3, DirectX 10; Up to 2 GB video memory; 3D acceleration is enabled by default |
The integration | VMDK, Microsoft VHD, HDD, QED, Vagrant, Docker | Requires an additional conversion tool for more VM types; VMware VSphere and Cloud Air (on VMware Workstation) |
VirtualBox guest additions versus VMware tools | Installed with the VBoxGuestAdditions.iso file | Install with the .iso file used for your VM (linux.iso, windows.iso, etc.). |
APIs for developers | API and SDK | Various APIs and SDKs |
costs and licenses | Free, under the GNU General Public License | VMware Workstation Player is free, while other VMware products require a paid license |
Software and hardware virtualization
VirtualBox supports software virtualization, but VMware does not.
Software virtualization emulates a complete computer system and runs guests on it. This type of virtualization allows you to run virtual machines that use a different platform than the host. The downside is that virtual machine performance is slower compared to hardware virtualization.
VirtualBox and VMware support hardware virtualization.
Hardware virtualization emulates hardware devices from a host. By executing the code directly on the hardware, you can increase the performance of the virtual machine.
To take advantage of hardware virtualization:
- The host computer must have Intel VT-x or AMD-V processor capabilities.
- You must enable hardware virtualizationUEFI/BIOS.
- You can only run guests on the same platform as the host.
operating system
The choice between the two virtualization platforms may be up to youoperating system host. While VirtualBox runs on a variety of operating systems, VMware has slight limitations.
You can installVirtualBoxTHELinux,Windows,Solaris,Mac operating system, IFreeBSD.
VMware-PlayerIVMware Workstationwork on itLinuxIWindows. If you haveMac operating systemYou must installVMware Fusion/Fusion Pro.
Both options support mostguest operating systems, includingLinux, Windows, Solaris, macOS and FreeBSD. The only difference is that VMware requires VMware Fusion/Fusion Pro to run macOS VMs.
user interface (UI)
VirtualBox has a graphical user interface (GUI) and a command line interface (CLI) called VBoxManage. The CLI interface allows management of virtual machines from the host command line, providing greater functionality.

VMware has a graphical user interface and a command line (VMware
). VMware Workstation has more user interface features compared to the simpler VMware Player GUI.

snapshots
Snapshots allow you to save the state of the VM and restore it later.
When you take a snapshot, you save a copy of the virtual machine disk file (VMDK). You can create multiple snapshots of a VM while it is running, saved, or shut down. There is no official limit on the number of snapshots. Note, however, that overloading can affect virtual machine performance.
You can create multiple snapshots of the same VM, each with a different virtual disk. This function is useful for testing because it allows you to easily return to a specific state.
VirtualBoxSupports snapshot whileVMwarehas this feature in its paid virtualization products (not VMware's free player).
Virtual Disk
As with other devices, you can emulate virtual disks that contain virtual machine data.
Format
Virtualization platforms can vary by typeFormat of the virtual diskSupport them.
VirtualBox supports:
- Virtual Disk Image (VDI) - used by default
- Virtual Machine Disk (VMDK) - developed by VMware
- Virtual Hard Disk (VHD) - Developed by Microsoft
On the other hand, VMware supports:
- Virtual Machine Disk (VMDK)
Therefore, VirtualBox is much more versatile when it comes to disk format.
mapping type
Virtual disks can bepre-assignedIdynamically assigned.
If youAssign a virtual disk in advance, reserve a specific amount of disk space for a specific virtual machine. This space cannot be used by the host or other guest machines.
Dynamically assignedVirtual disks do not occupy fixed storage space from the start. They grow over time, taking up as much space as they need until they reach their allotted maximum size.
VirtualBox supports preallocated files (referred to asFest) and dynamically assigned (so-calledassigned) virtual disks.
VMware also supports pre-allocationbig reserves) and dynamically assigned (so-calledThin Provisioning).

Virtual Network Modes
You can configure each network adapter separately so that your virtual machine runs in the selected network mode.
VirtualBoxoffers the following network modes:
- Not included
- Network Address Translation (NAT)
- NAT network
- Bridged Network
- internal network
- Host-only network
- General network
- Tunel UPD
- Virtually Distributed Ethernet (VDE)
For a detailed description of each network mode, contact your official Oracle representativeVirtualBox manual.
VMwaresupports:
- Network Address Translation (NAT)
- Host-only network
- Virtual Network Editor (on VMware Workstation and Fusion Pro)
Support for USB devices
You can connect a USB stick to a guest computer simply by plugging it into the host. Both VirtualBox and VMware support USB devices.
VirtualBoxsupports USB 1.0 but requires installation of VirtualBox expansion pack for USB 2.0 and USB 3.0.
VMwareAllows use of up to 2 USB devices and hasConnection USBenabled by default. Whether a virtual machine supports USB 2.0 and 3.0 mainly depends on the host.
Graphic 3D
VirtualBoxrequires manually enabling 3D acceleration on the VM to support 3D graphics. It only supports 3D graphics up to OpenGL 3.0, Direct3D 9. The video memory is limited to 128 MB.
VMwarehas the upper hand when it comes to handling 3D graphics. The platform offers 3D graphics with DirectX 10 and OpenGL 3.3 support for all of its products. In addition, it offers up to 2 GB of video memory.
The integration
In addition to the various virtual hard disk formats (VMDK, VHD,hard diskI QED),VirtualBoxIt also provides access to integration tools like Vagrant and Docker.
VMwareIt doesn't support that many disk formats. To run VMs in a format other than VMware's VMDK, you need an additional conversion tool. The software is integrated with VMware vSphere and Cloud Air, but only for VMware Workstation.
VirtualBox Guest Additions and VMware Tools
You can increase your performanceVirtualBoxvirtual machines through installationExtras for guests. It consists of device drivers and system applications that are installed in the virtual machine.
You can install VirtualBox Guest Additions with itVBoxGuestAdditions.isoFile on any guest operating system. Note that there is a Guest Additions version for every version of VirtualBox. Features include smooth windows, shared folders, mouse cursor integration, shared clipboard, time sync, and more.
VMware has its own tool for improving guest operating systems –VMware-Tools. Unlike guest postsVMware-ToolsA separate ISO image is stored in the application directory for each supported operating system (linux.iso, windows.iso, solaris.iso, etc.).
Without this tool, virtual machine performance would not include features like high video resolution and displaynetwork speed, copy and paste and drag and drop options, etc.
APIs for developers
If you want to create applications that communicate and interact with virtual machines, you can use APIs and SDKs. Both virtualization platforms allow you to do this, while VMware Workstation also provides additional features such as the Eclipse plugin and VMware Studio.
costs and licenses
VirtualBoxis free, open-source virtualization software available under the GNU General Public License (GPL), version 2. You may use them for personal, educational, or commercial use at no additional cost. In addition, the expansion pack is completely free.
VMwarehas several virtualization products:
- VMware-PlayerIt is free for personal and educational use. However, if you plan to use the platform commercially, a $149.99 license is required.
- VMware Pro WorkstationA license fee of $199.00 is charged for use in large companies and projects.
- VMware-Fusion(used on macOS hosts) has a one-time license fee of $159.99.

Note:Check out our guideHow to Install Rocky Linux on Virtualbox.
How to choose?
The most visible difference between the two is the licensing:
- VirtualBox is free and open source.
- VMware is free for personal use only.However, the free version has limited features for personal and educational use. For example, clones and snapshots are not supported.
However, if performance is a key factor in a particular use case, investing in a VMware license would be a more sensible choice.VMware VMs run fasterthan their VirtualBox counterparts. This difference may not be as noticeable on a smaller scale, but it does impact performance in enterprise projects.
The decision depends on what you want from your VMs. For example, do you want more format options for virtual hard drives or better 3D graphics? Both options have pros and cons, so it's worth weighing up each feature.
Based on their characteristics, we propose the following virtualization platform for specific use cases:
For those looking for a free solution, use:
- VirtualBox
For educational purposes use:
- VirtualBox
- VMware Workstation Player
For a smaller project use:
- VirtualBox
For medium sized projects use:
- VirtualBox
- VMware Pro Workstation
For large projects use:
- VMware Pro Workstation
For companies aiming for high performance, use:
- VMWare Esx
Application
This article provides a detailed comparison between VirtualBox and VMware, two of the most popular virtualization platforms.
After examining all factors, you should make the right decision for your application.
FAQs
How do VMware and VirtualBox compare? ›
VirtualBox and VMware are both connected to virtualization. The primary distinction between VirtualBox and VMware is that VirtualBox is a free and open-source hypervisor which Oracle Corporation creates. In contrast, VMware is a cloud computing and platform virtualization software and services, provider.
Which is better VMware vs VirtualBox? ›VirtualBox supports a variety of virtual disc types (VMDK, VHD, HDD, and QED), as well as integration tools like Vagrant and Docker whereas VMware does not support a large number of different disc formats. Virtual machines created by VMware are faster than those created by VirtualBox.
Which is easier to use VMware or VirtualBox? ›VMware Vs VirtualBox: Key differences
There is large scope for the various operating system in VirtualBox while VMware has a narrow scope also the interface of VirtualBox is easy to use while on the flipside the interface of VMware is quite complex and hard.
VirtualBox has limited support for 3D graphics (up to OpenGL 3.0, Direct3D 9). 3D acceleration must be enabled in the VM settings manually. A maximum 128 MB of video memory is supported. Graphics drivers must be installed on the host machine, and VirtualBox Guest Additions must be installed on the guest machine.
What are the advantages of VirtualBox over VMware? ›VirtualBox supports software virtualization, while VMware doesn't. Software virtualization emulates a complete computer system and runs guests on top of it. This type of virtualization allows you to run virtual machines that use a different platform than the host.
What is the difference between Oracle VM and VMware? ›Oracle VM supports hard partitioning which can significantly reduce software applications licensing costs. VMware vSphere is a powerful and complete server virtualization platform that allows its users to create and manage virtual data centers and machines.
Is VirtualBox good enough? ›Oracle VM VirtualBox is the #5 ranked solution in best Server Virtualization Software. PeerSpot users give Oracle VM VirtualBox an average rating of 7.8 out of 10. Oracle VM VirtualBox is most commonly compared to Proxmox VE: Oracle VM VirtualBox vs Proxmox VE.
Why is VirtualBox the best? ›VirtualBox is excellent if you only need to run VMs on a few machines and want access to a command line interface in addition to the GUI. Both solutions offer a “snapshot” feature that has proven highly popular as a response to one of the inherent challenges of virtualization: mistakes.
Which VM to choose? ›Choosing the right type of VM is as simple as matching your workload against the type of VM designed to run that workload. Example 1: If you're in a testing/development phase, run low traffic web servers or host a small-to-medium database, the General Purpose VM Type would be a good choice.
What are three 3 advantages of using a virtual machine? ›Benefits include increased performance and speed, load balancing and reduced costs. Storage virtualization also helps with disaster recovery planning, as virtual storage data can be duplicated and quickly transferred to another location, reducing downtime.
Is VirtualBox the best virtual machine? ›
Most Versatile Virtual Machine Software
The best free virtual machine software for Linux is also the most versatile for other operating systems. Oracle VM VirtualBox is an open-source software that supports the widest range of guest operating systems of any virtual machine software on this list.
In terms of security, it is biased on both sides; VMWare is closed-source meaning only the employees have access to the source code which does make it harder to exploit (since the attacker cannot just read the source code to find problems but would have to spend lots of time manually reversing and testing on repeat), ...
What are the disadvantages of VMware? ›One of the main drawbacks of VMware is its cost. VMware products are not free, and you may need to purchase licenses, subscriptions, or support plans to use them. VMware also requires more resources than Hyper-V, as it runs on top of an existing operating system, rather than being part of it.
Why do people use VirtualBox? ›VirtualBox allows any system to install and operate as many virtual machines as its memory and disc space allow. Depending on the host system's configuration, one can use this solution to deploy anything from desktop-class machines and small embedded systems to cloud environments and large datacenter deployments.
What are the risks of using Oracle VirtualBox? ›- You Don't Update the Virtual Machine. ...
- File Sharing Is Enabled Between Host and VM. ...
- Using a Vulnerable Application. ...
- Using an Outdated VirtualBox Version.
- Personalization: There is great flexibility and personalization with virtual machines. ...
- Virtualization: ...
- Backup by VM at a time: ...
- Easy Recover/Failover: ...
- Run multiple Operating Systems: ...
- OS and Application Updates: ...
- The Bottom Line:
Containers are more lightweight than VMs, as their images are measured in megabytes rather than gigabytes. Containers require fewer IT resources to deploy, run, and manage. Containers spin up in milliseconds. Since their order of magnitude is smaller.
Can we use VirtualBox and VMware at the same time? ›It is possible. The major caveat I've run into is that usually only one hypervisor can use the hardware acceleration features offered by modern motherboards/chipsets, so one hypervisor may have to run in software virtualization mode, which can limit you VM guest choices.
What is VMware in simple words? ›VMware is a virtualization and cloud computing software provider based in Palo Alto, Calif. Founded in 1998, VMware is a subsidiary of Dell Technologies. EMC Corporation originally acquired VMware in 2004; EMC was later acquired by Dell Technologies in 2016.
Which three are benefits of Oracle VMware solution? ›- Complete customer control. Retain full root access and administrative control of VMware environments. ...
- Migrate applications without modification. ...
- Independent scaling of compute and storage. ...
- Predictability across operations, performance, and costs.
What is the difference between VMware template and virtual machine? ›
Whereas a template serves as a baseline image for creating multiple VMs, a VM clone is an exact copy, sharing many of the hardware and software configuration settings, including unique identifiers, which can create interoperability issues.
How much RAM should I allocate to VirtualBox? ›Create New Virtual Machine
VirtualBox recommends that the memory size be at least 512MB, however, the more memory you make available to the VM, the smoother and more powerful it will be. As a rule of thumb, 1/4 of the amount of memory you have on your computer should be just fine.
Yes, it can. You can see below that my laptop has 16Gb of physical RAM and yet the VM allocates a maximum amount of 1Tb. But if the VM uses over the physical RAM, the host OS will use the swap so it will get very slow.
Why does VirtualBox use so much CPU? ›Your processor does not offer hardware-assisted virtualization so VirtualBox is using software-based techniques, which will use more CPU time and make everything slow. Read more about it here.
Does VirtualBox slow down PC? ›Another reason for the slow performance of VirtualBox, especially if you are using a laptop, is the power plan you use for how your device consumes and saves power. In order for VirtualBox to run smoothly and without delays, Power Plan must be set to High Performance.
What are the disadvantages of using a virtual machine? ›- Compatibility issue. Migrating existing systems into VM environments can be difficult due to compatibility issues between software versions used across different platforms. ...
- Performance overhead. ...
- Hardware limitations. ...
- Complexity. ...
- Security risks. ...
- License cost. ...
- Single point of failure.
VirtualBox
Then VirtualBox is a good choice because it supports an amazingly wide selection of host and client combinations. Windows from XP onwards, any Linux level 2.4 or better, Windows NT, Server 2003, Solaris, OpenSolaris and even OpenBSD Unix. There are even people that nostalgically run Windows 3.
Answer: Some users have claimed that they find VMware to be faster compared to VirtualBox. Actually, both VirtualBox and VMware consume a lot of resources from the host machine. Therefore, the physical or hardware capabilities of the host machine are, to a great extent, a deciding factor when virtual machines are run.
What size VM do I need? ›Workload type | Maximum users per vCPU | Minimum vCPU/RAM/OS storage |
---|---|---|
Light | 6 | 8 vCPUs, 16-GB RAM, 32-GB storage |
Medium | 4 | 8 vCPUs, 16-GB RAM, 32-GB storage |
Heavy | 2 | 8 vCPUs, 16-GB RAM, 32-GB storage |
Power | 1 | 6 vCPUs, 56-GB RAM, 340-GB storage |
Generally speaking, there are three typical classes of virtual machine (VM) architecture -- the hypervisor, host-based virtualization and para-virtualization, which are differentiated by the position of the virtualization layer. The hypervisor is also known as the Virtual Machine Monitor (VMM).
Why would anyone want to use a virtual machine? ›
Virtual machines are best for running multiple applications together, monolithic applications, isolation between apps, and for legacy apps running on older operating systems. Containers and virtual machines may also be used together.
What are the pros and cons of virtual machines? ›- Pros of Virtualization. Uses Hardware Efficiently. Available at all Times. Recovery is Easy. Quick and Easy Setup. ...
- Cons of Virtualization. High Initial Investment. Data Can be at Risk. Quick Scalability is a Challenge.
The main purpose of VMs is to operate multiple operating systems at the same time, from the same piece of hardware. Without virtualization, operating multiple systems — like Windows and Linux — would require two separate physical units.
What is best virtual machine to run Windows? ›- Best Overall: VMware Workstation.
- Best for Mac Users: VMware Fusion.
- Best Free Option: Oracle VM VirtualBox.
- Best for Running Windows and macOS: Parallels Desktop.
- Best for (Some) Windows 10 Users: Hyper-V Manager.
- Best for Linux Users: QEMU.
VirtualBox, in contrast, is a type 2 hypervisor and can allow users to have quick access to the alternative guest OS alongside the primary host's operating system.
What is the best host for VirtualBox? ›Linux Mint is often considered the best Linux distro for VirtualBox, and rightfully so. That's because it comes with an intuitive and beautiful user interface. Above all, it's beginner-friendly and user-oriented. You can also customize the look and feel of the interface by using themes and plugins.
Do you need antivirus for VirtualBox? ›The answer is yes, as virtual machines are just as vulnerable to viruses and malware as physical machines. Virtual machines are a great way to save money and resources, but they can also be a target for malicious software. To protect your virtual machine, you should install antivirus software and keep it up to date.
What is the best virtual machine for viruses? ›VirtualBox and Hyper-V are good free options. If you want to set up a headless server for your lab, you'll probably like VMware vSphere Hypervisor (formerly called ESXi), which is also free. If using VMware Workstation, you'll need the commercial version: Workstation Pro for Windows and Linux or Fusion Pro for macOS.
Can I run malware in VirtualBox? ›Is it safe to run viruses in VirtualBox? Depends, if you are running a virtual machine on windows, while the virtual machine is open there is a small chance that the virus could migrate over to windows. If your running a virtual machine on Linux I would say it's 99.9% impossible to get the main system infected.
Is VMware outdated? ›As of October 15, 2022, VMware ESXi 6.5 and VMware ESXi 6.7 reached end-of-life and will only receive technical support but no security updates, putting the software at risk of vulnerabilities. The company analyzed data from 6,000 customers and found 79,000 installed VMware ESXi servers.
Why not to use virtual machines? ›
Disadvantages. Virtual machines are less efficient than real machines because they access hardware indirectly. Running VM software on top of the host operating system means that it will have to request access to storage and memory from the physical device.
Can I trust VirtualBox? ›Both VirtualBox and VMWare are safe, reputable hypervisors. A website that looks "old" is not an indicator of malice, and sometimes the most reputable websites look very old indeed. VMWare has more closed source components than VirtualBox, which can make it less trustworthy as a result of a closed design.
Does VirtualBox always use RAM? ›VirtualBox does not use the hard disk for virtual RAM. It uses the computer's physical RAM for virtual RAM. In the screenshot 4096 MB of the available 16384 Base Memory (the physical RAM) is allocated to the guest OS and the remainder of the physical RAM is available to be used by the host OS.
Who owns VirtualBox? ›VirtualBox was originally created by InnoTek Systemberatung GmbH, which was acquired by Sun Microsystems in 2008, which was in turn acquired by Oracle in 2010. VirtualBox may be installed on Microsoft Windows, macOS, Linux, Solaris and OpenSolaris.
How do I protect my VirtualBox? ›- General Virtual Machine Protection.
- Use Templates to Deploy Virtual Machines.
- Minimize Use of the Virtual Machine Console.
- Prevent Virtual Machines from Taking Over Resources.
- Disable Unnecessary Functions Inside Virtual Machines. Remove Unnecessary Hardware Devices. Remove Unnecessary Hardware Devices.
In case your organization is making use of the Oracle VM VirtualBox Extension Pack software for production or commercial purposes, then such use is required to be licensed through a commercial license.
What are the major differences between Hyper V VMware workstation and VirtualBox? ›Hyper-V is a type 1 hypervisor while VirtualBox is a type 2 hypervisor. Hyper-V can only be installed on Windows-based systems, while VirtualBox is a multiplatform product. Hyper-V supports clustering features such as failover clustering and load balancing.
What is the advantage of virtual machine vs container? ›VMs solve infrastructure problems by letting organizations get more out of servers and facilitate limited workload portability. Containers solve application problems by improving DevOps, enabling microservices, increasing portability, and further improving resource utilization.
What is benefit of using VirtualBox? ›VirtualBox allows any system to install and operate as many virtual machines as its memory and disc space allow. Depending on the host system's configuration, one can use this solution to deploy anything from desktop-class machines and small embedded systems to cloud environments and large datacenter deployments.
What is the most stable version of VirtualBox? ›The recommended VirtualBox version for Windows is VirtualBox 7.0.
What is the main difference between containers and VM virtual machine? ›
Key differences: containers vs. virtual machines. Containers virtualize the operating system so the application can run independently on any platform. Virtual machines go beyond that to virtualize physical machines, so you can use your hardware resources efficiently.
What can VMware do that Hyper-V Cannot? ›For example, while VMware can use more logical CPUs and virtual CPUs per host, Hyper-V can accommodate more physical memory per host and VM.
How do I know if my VM is Hyper-V or VMware? ›- Click Start > Run.
- Type msinfo32 and press Enter.
- In the right pane, look for System Manufacturer for 'VMware, Inc. ' If this is present, you are running within a virtualized platform, and cannot install another virtualization product on top of it.
There are three main types of server virtualization: full-virtualization, para-virtualization, and OS-level virtualization.