VMware ESXi and vSphere Cluster Management

VMware Workstation Player Glossary: Virtualization, Networking, Storage, and VM Management Terms

Learn essential VMware Workstation Player terms for virtual machines, networking modes, virtual disks, VMware Tools, USB devices, and troubleshooting.

This glossary explains the core terminology used in VMware Workstation Player. It covers virtualization fundamentals, VM files, storage, installation media, networking, host-guest integration, CPU and USB settings, and diagnostics.

Virtualization fundamentals

Virtual machine

A virtual machine (VM) is a software-based computer. It runs an operating system and applications as if it were a separate physical computer, while its hardware is represented and managed by software.

The physical host computer is the real computer providing CPU, memory, storage, and hardware devices. Its host operating system is the operating system installed directly on that computer. The guest operating system is the operating system installed inside a VM.

Hypervisor

A hypervisor is the software layer that creates and manages VMs. It presents virtual processors, memory, disks, network adapters, and other devices to guest operating systems while allocating resources from the host.

Term	Definition	Where it runs or applies	Example or implication
Type 1 hypervisor	A hypervisor that runs directly on physical hardware.	Between the hardware and guest systems.	Common in dedicated server virtualization.
Type 2 hypervisor	A hypervisor that runs as an application on a conventional host operating system.	Above the host operating system.	VMware Workstation Player is a type 2 hypervisor.
Intel VT-x	Intel hardware-assisted virtualization technology.	Processor, firmware, host, and VM execution.	It may need to be enabled in UEFI/BIOS firmware.
Virtual SMP	The ability to assign multiple virtual processors to a VM.	VM processor configuration.	Useful for parallel workloads, but consumes more host CPU capacity.

Intel VT-x may be unavailable if it is disabled in firmware, unsupported by the processor, unavailable to the host operating system, or reserved by another virtualization layer. Configuring multiple virtual CPUs through Virtual SMP does not create additional physical CPU power; it assigns more scheduling capacity to the guest. Avoid giving a VM more virtual CPUs than its workload and host can reasonably support.

VM identity, configuration, and packages

UUID

A Universal Unique Identifier (UUID) is an identifier used to distinguish one VM from another. It helps virtualization software and related tools identify a VM even when several VMs have similar names.

Configuration and working files

The .vmx file is the VM's configuration file. It records settings such as virtual hardware, memory, processor allocation, attached devices, and networking choices.

A .vmdk file is a VMware virtual disk file. Depending on its configuration, a virtual disk can consist of one file or multiple files. It is presented to the guest as a disk drive.

The VM working directory is the directory used for the VM's configuration, virtual disks, logs, and temporary or state-related files. It can contain suspended-state files, snapshot-state files, memory backing files, and redo-log files. Do not treat a VM as only its visible name in the Player interface; its working directory contains the files needed to operate it.

Virtual appliances

A virtual appliance is a prebuilt, preconfigured VM distributed for deployment. Appliances commonly include a guest operating system, applications, and initial VM settings.

Common appliance packaging uses OVF-style files or an OVA package. An OVA is a packaged virtual appliance distribution, usually containing configuration information and one or more virtual disks in an archive. Other distributions may provide an archive containing a virtual disk and a VM configuration file. Verify the source and inspect the supplied configuration before importing an appliance.

File or extension	Purpose	Typical location	When it is created or used
`.vmx`	VM configuration.	VM working directory.	Used whenever the VM is opened or run.
`.vmdk`	Virtual disk containing guest data.	VM working directory or a configured storage location.	Created when a virtual disk is created or imported.
`vmware.log`	Runtime messages, warnings, and diagnostic information.	VM working directory.	Written while the VM starts and runs.
`.vmss`	Saved suspended execution state.	VM working directory.	Created when a VM is suspended.
`.vmsn`	Snapshot state information.	VM working directory or snapshot-related storage.	Used when snapshot state is recorded.
`.vmem`	Backing file for VM memory.	VM working directory.	May be created for suspend, snapshot, or related state operations.
Redo-log files	Record changed disk blocks separately from a base virtual disk.	VM working directory or snapshot storage.	Used by snapshot or disk-state mechanisms.

Virtual disks and storage maintenance

Virtual disk

A virtual disk is one or more files on the host that the guest sees as a disk drive. It normally contains the guest operating system, installed software, and user data. The typical VMware extension is .vmdk.

Disk operations

Operation	Purpose	Effect on virtual disk capacity	Guest-side follow-up	Primary caution
Compact	Reclaims host space represented by unused blocks.	May reduce host-side storage use; it does not reduce the guest's maximum capacity.	Often requires suitable free-space conditions inside the guest.	Eligibility depends on disk type, snapshots, free space, and guest preparation.
Defragment	Reorganizes virtual disk data to improve its layout and potentially performance.	Does not increase the disk's maximum capacity.	Usually no partition resize is required.	It can require temporary host space and is not a substitute for guest file-system maintenance.
Expand	Increases the virtual disk's maximum capacity.	Increases the capacity visible to the virtual hardware.	Extend the guest partition and file system.	Back up important data and ensure the VM is in an appropriate state before changing storage.

Compacting is not the same as deleting files in the guest. Removing files may create free blocks inside the guest without immediately releasing corresponding host storage. When supported, prepare or zero unused guest space as appropriate, then use Player's virtual disk maintenance controls and verify the host-side result.

Expanding a .vmdk only makes additional virtual capacity available. The guest still needs a partition and file-system operation before it can use that space. For example, after expansion, a Windows guest may need its volume extended, while a Linux guest may need partition and file-system resizing with tools appropriate to its layout.

Guest installation and boot media

ISO image

An ISO image is a file-based representation of the contents of an optical disc. ISO files are commonly used as installation media for operating systems and large software distributions.

To install a guest, attach the ISO to the VM's virtual CD/DVD device and configure the VM to boot from that device when necessary. If direct access to a physical optical drive causes problems, Legacy Emulation Mode is a compatibility setting that can help with optical-drive communication in supported configurations.

Easy Install

Easy Install is an installation automation feature for supported guest operating systems. It can prefill or automate parts of installation, such as user information and initial configuration. A manual ISO installation gives you more direct control and is useful when the guest is unsupported or when you need custom partitioning.

Damn Small Linux is a historically notable, very small Linux distribution often used as a lightweight example for VM learning and testing. Its small footprint makes it useful for demonstrating boot media and basic guest operation, although current hardware and software compatibility should be checked.

VM lifecycle and state

Suspend saves a VM's current execution state so it can later resume from approximately the same point. The saved state can include memory contents, processor state, device state, and related execution information.

Normal guest shutdown: The guest operating system closes applications and shuts down cleanly. Starting the VM later performs a normal boot.
Suspend: The running session is saved for later resumption. State files are written to the VM working directory.
Power off: The VM is stopped without a normal guest shutdown. Unsaved guest data may be lost, much like removing power from a physical computer.

Suspended-state files such as .vmss and memory-related files such as .vmem can consume substantial host storage, especially when the VM has a large amount of assigned memory. Inspect the VM working directory if a suspend or resume operation uses more storage than expected or takes a long time.

Networking modes and virtual components

Core networking terms

A virtual network adapter is the guest-facing network interface created for a VM. A virtual switch connects virtual network participants, such as VMs, host adapters, and virtual networking services.

A NAT device forwards traffic between a private VM network and an external network while translating addresses. A virtual DHCP server assigns IP addresses and related network settings to VMs on applicable NAT and host-only networks.

Mode	Guest IP address source	External network identity	Host-to-guest connectivity	External network reachability	Typical use case
Bridged networking	Usually the physical network's DHCP service or a manually configured LAN address.	The VM acts as an independent device with its own network identity and normally its own IP address.	Usually available through the physical LAN, subject to firewalls and network policy.	Directly connected through the selected host physical adapter.	Use when the guest must appear as a separate computer on the LAN.
NAT networking	Usually a private address from the virtual DHCP server.	The guest uses the host's shared external network identity through the NAT device.	The host can normally communicate with the guest on the private virtual network.	Usually available for outbound connections, while unsolicited inbound access requires configured forwarding or other support.	Use when the guest needs web or external access without an independent LAN presence.
Host-only networking	Usually a private address from the virtual DHCP server or a manually configured private address.	No normal direct external-network identity.	Provides an isolated network between the host and connected VMs.	Normally unavailable unless additional routing is deliberately configured.	Use for isolated labs, testing, and host-to-guest communication.

Choose the network adapter mode according to the desired connectivity model. For a web-connected test VM, choose NAT. For a guest that must be visible as a separate LAN device, choose bridged networking. For an isolated host-to-VM lab, choose host-only networking. An unexpected IP address often indicates that the selected mode, virtual DHCP service, or adapter connection state differs from the intended design.

Host-to-guest integration

Feature	What it enables	Common prerequisite	Limitations or compatibility notes
VMware Tools	Guest drivers and utilities for better display, input, performance, and management.	Install the suitable tools or supported guest utilities.	Features vary by guest operating system and tools version.
Copy and Paste	Transfers text and, where supported, files through a shared clipboard.	Compatible VMware Tools and enabled integration.	May be restricted by guest support, security policy, or application behavior.
Drag-and-Drop	Moves files between host and guest using the desktop interface.	Compatible VMware Tools and desktop integration.	Not supported in every guest desktop or for every file type.
Shared folders	Exposes selected host directories to the guest through a managed integration mechanism.	VMware Tools or supported guest tools, plus enabled shared folders.	Access path and permissions depend on the guest operating system.
Unity Mode	Displays guest application windows alongside host desktop applications instead of inside a conventional VM window.	Guest support and VMware Tools.	Availability and behavior depend on the guest desktop environment.
Autologin	Automatically signs in to a supported Windows guest.	Supported Windows guest and configured credentials.	Convenient but reduces the protection provided by manual sign-in.
Enhanced Virtual Keyboard	Improves handling for non-US layouts and keyboards with additional keys.	Supported host, guest, and keyboard configuration.	Layout problems can also arise from mismatched host and guest keyboard settings.

Copy and Paste provides clipboard integration for text and, where supported, files. Drag-and-Drop transfers files through the desktop interface. Shared folders provide a more managed way to expose selected host folders. These features depend on guest support and VMware Tools; they are not guaranteed merely because a VM is running.

VMware Tools

VMware Tools is a collection of guest-installed drivers and utilities. It can improve display handling, mouse input, time coordination, performance, device management, and integration features such as clipboard sharing, drag-and-drop, shared folders, and Unity Mode.

Some historical Linux VMware Tools installation workflows required Perl, a cross-platform programming language. Modern Linux guests may instead use distribution packages or open-source guest tools, so follow the guest distribution's supported method rather than assuming a legacy installer is required.

CPU virtualization and processors

Intel VT-x is Intel's hardware-assisted virtualization extension. The host may require the corresponding firmware option to be enabled in UEFI/BIOS. Hardware virtualization must also be supported and available to the host operating system.

Virtual SMP assigns multiple virtual processors to a VM. More virtual CPUs can help a guest workload that runs several tasks in parallel, but they also increase scheduling and resource demands. Start with an appropriate number for the workload, monitor host contention, and avoid excessive oversubscription—the practice of assigning more virtual CPU capacity than the host can efficiently run at the same time.

Keyboard and USB device handling

An USB human interface device (USB HID) is a USB device used for human input. Examples include keyboards, mice, and game controllers. Core keyboard and mouse devices are commonly retained by the host so that the host desktop remains usable; therefore, they may not appear as ordinary removable devices that can be connected to a guest.

Enhanced Virtual Keyboard improves handling of international layouts and keyboards with extra keys. It is distinct from USB passthrough: the feature improves virtual keyboard interpretation, while passthrough gives a guest access to a physical USB device when supported.

An isochronous USB device or isochronous transfer requires timing-sensitive delivery of data. Webcams, speakers, and some modems are examples. USB passthrough compatibility depends on the host, guest, device type, controller, VMware product support, and timing requirements. A webcam or audio device may therefore behave differently from a simple storage device or controller.

Logs and diagnostics

The VM message log is a per-VM source of warnings and operational information. The primary file is commonly named vmware.log and is stored in the VM's working or configuration directory.

Log entries can help investigate display issues, driver failures, virtual-device connection errors, startup failures, and network problems. Open the log from the VM directory, review entries near the time of failure, and correlate them with recent configuration changes.

Practical configuration examples

Install a Linux guest from an ISO

Obtain a suitable Linux ISO image.
Open the VM's CD/DVD device settings and attach the ISO.
Configure the VM to boot from the virtual optical drive if required.
Choose Easy Install when the guest is supported and automation is appropriate; otherwise perform a manual installation.
Install the appropriate VMware Tools package or supported guest utilities after the operating system is running.

Choose a network mode

Choose NAT for outbound internet access using the host's shared network identity.
Choose bridged when the VM needs its own address and identity on the physical LAN.
Choose host-only for an isolated network between the host and VMs.

Reclaim storage after deleting guest files

Deleting files inside a guest does not necessarily reduce host-side use of a virtual disk. Check the virtual disk type and current state, prepare unused guest space if required by the supported workflow, and use the compact operation when eligible. Keep backups before maintenance operations.

Increase guest storage

Use Player's disk controls to expand the virtual disk, then extend the guest partition and file system. If the guest still reports the original size, the virtual disk expansion may have succeeded while the guest-side resize has not been completed.

Transfer a project file

Use shared folders for a managed, repeatedly accessible host directory. Use drag-and-drop for a convenient desktop transfer, or Copy and Paste where supported. If these features fail, verify that VMware Tools or supported guest tools are installed and running.

Suspend a development VM

Suspend the running VM when you need to resume the same session later. Check the VM working directory afterward: .vmss, .vmem, and related state files can consume storage comparable to the VM's assigned memory and active state.

Connect a USB peripheral

Use removable-device controls to connect a supported USB device to the guest. A webcam may be an isochronous device with timing-sensitive requirements, while a keyboard or mouse is usually a USB HID retained by the host. If passthrough fails, check device support and host and guest permissions.

Configure multiple guest CPUs

Set the virtual processor count in the VM's processor settings, run the CPU-intensive workload, and compare performance with a single-vCPU configuration. More virtual CPUs are not automatically faster if the host is CPU-constrained.

Troubleshooting by symptom

Hardware virtualization is unavailable: Check whether Intel VT-x or the equivalent firmware setting is enabled, whether the host supports it, and whether another host-level virtualization layer is using or blocking access.
No network access or an unexpected IP address: Confirm the selected bridged, NAT, or host-only mode, the virtual network adapter's connection state, DHCP availability, and whether the expected network is private or physical.
A bridged guest cannot be reached from the LAN: Verify that bridging uses the correct physical host adapter, that the guest has a valid LAN address, and that firewalls or network security policies allow the traffic.
Copy/paste, drag-and-drop, shared folders, or Unity Mode fails: Verify compatible VMware Tools or guest utilities, enabled VM settings, running integration services, and guest support.
The host disk remains full after guest files are deleted: Review the virtual disk type, unused-space preparation, snapshots or redo logs, and compact eligibility. Guest deletion alone does not necessarily shrink host storage.
New virtual disk capacity is unavailable: Confirm expansion of the .vmdk, then extend the guest partition and file system.
Resume is slow or suspend uses unexpected storage: Inspect the VM working directory for .vmss, .vmem, and related state files.
A webcam, audio device, or USB peripheral fails: Check USB passthrough support and distinguish timing-sensitive isochronous devices from host-reserved USB HIDs.
Keyboard layouts or special keys behave incorrectly: Review Enhanced Virtual Keyboard settings, host and guest layouts, and whether the physical input device is retained by the host.
The virtual optical drive fails: Confirm the ISO or physical drive attachment and try Legacy Emulation Mode when direct optical-drive communication causes compatibility problems.
A display, driver, or device error appears: Review vmware.log in the VM directory, correlate entries with the failure time, and verify guest drivers and VMware Tools.

For a compact reference, see the VMware Workstation Player glossary.