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# Virtualization enumerations

Control the caching modes, disk synchronization, and macOS auxiliary storage options of VMs.

## Discussion

These are values you use to control aspects of the operation of the virtual drives for guest VMs and the auxiliary storage of macOS guest VMs.

## Topics

### Virtual disk image caching modes

[`VZDiskImageCachingMode`](/documentation/Virtualization/VZDiskImageCachingMode)

An integer that describes the disk image caching mode.

### Virtual disk synchronization modes

[`VZDiskImageSynchronizationMode`](/documentation/Virtualization/VZDiskImageSynchronizationMode)

An integer that describes the disk image synchronization mode.

[`VZDiskSynchronizationMode`](/documentation/Virtualization/VZDiskSynchronizationMode)

Values that describe the synchronization modes available to the guest OS.

### Mac-specific auxiliary storage options

[`VZMacAuxiliaryStorage.InitializationOptions`](/documentation/Virtualization/VZMacAuxiliaryStorage/InitializationOptions)

Options you can set when creating new auxiliary storage.

### Extensible firmware interface (EFI) signatures

[`VZEFISignature`](/documentation/Virtualization/VZEFISignature-swift.enum)

### Rosetta availability states

[`VZLinuxRosettaAvailability`](/documentation/Virtualization/VZLinuxRosettaAvailability)

Constants that describe the availability and installation status of Rosetta.

### Virtualization error codes

[`VZError.Code`](/documentation/Virtualization/VZError/Code)

Errors you might encounter when configuring or using a virtual machine.

### VM states

[`VZVirtualMachine.State`](/documentation/Virtualization/VZVirtualMachine/State-swift.enum)

The execution states of the VM.


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