VMware ESXi and vSphere Cluster Management

How to Add a New Virtual Hard Disk in VMware Workstation Player

Learn how to add a new virtual hard disk to an existing VMware Workstation Player VM, choose disk settings, and initialize, partition, and format it in the guest OS.

Purpose and expected result

Adding a virtual hard disk gives an existing virtual machine additional storage. VMware stores the disk as a file, or group of files, on the host operating system and presents it to the guest operating system as a physical blank drive.

The disk is initially empty. Before the guest can save files, you normally must initialize it, create a partition or volume, format it with a guest-supported filesystem, and assign a drive letter or mount point.

Prepare before changing virtual hardware

  1. Select the target virtual machine in the VMware Workstation Player library.
  2. Power off the virtual machine before changing hardware settings when Player requires the VM to be shut down. Do not assume that suspending or pausing the VM is equivalent to powering it off.
  3. Check the host volume where the virtual machine files are stored. It must have enough free capacity for the new disk, its possible growth, and normal host operating system activity.
  4. Back up important guest data, or confirm that an appropriate recovery method such as a tested backup or snapshot-based procedure is available. Storage changes should not replace a real backup.

Open Virtual Machine Settings

Use the following VMware Workstation Player navigation:

Select virtual machine > Player > Manage > Virtual Machine Settings > Hardware > Add > Hard Disk

Virtual Machine Settings is the VMware interface for viewing and changing a VM's virtual hardware. On the Hardware tab, select Add to launch the New Hardware wizard. Select Hard Disk as the device type.

Choose a virtual disk controller type

A controller type determines how the guest operating system sees the disk and how many virtual devices can be attached. The appropriate choice depends on guest operating system compatibility and the VM's existing virtual hardware configuration.

IDE: Historical maximum of 4 attached devices per virtual machine. Use it only when compatibility with an older guest or existing configuration requires it.

SCSI: Historical maximum of 60 attached devices. This is the recommended general-purpose choice for a new virtual disk from the source material.

SATA: Historical maximum of 120 devices. The layout supports up to 4 controllers with up to 30 devices per controller.

For a typical secondary data disk, SCSI is a practical starting point. If the guest cannot use the selected controller, review its storage support and the VM's existing configuration before choosing another type.

Create a new virtual disk

  1. In the New Hardware wizard, choose the required disk type: IDE, SCSI, or SATA.
  2. Select Create a new virtual disk. Do not select the option for attaching an existing disk file unless you intend to reuse a disk already stored on the host.
  3. Continue to the capacity and storage options.

The wizard creates a virtual disk file on the host. VMware then presents that file to the guest as a physical blank drive. Creating the host-side file does not create a filesystem inside the guest.

Set the virtual disk capacity

Choose the maximum virtual disk size according to the expected workload, data growth, and capacity of the host storage volume. Consider the largest dataset the guest may need, not only the amount of data it contains today.

Configured virtual capacity is the maximum size visible to the guest. It is not necessarily the amount of host storage consumed immediately. A disk configured as 100 GB can initially use less than 100 GB on the host when it is not preallocated, then grow as the guest writes data.

Choose disk space allocation

Allocate all disk space now: Reserves the full configured capacity on the host immediately. This can provide more predictable storage use and may improve performance, especially during frequent large data transfers into the guest. The trade-off is that the entire amount of host storage must be available at creation time.

Do not allocate all disk space now: Allows the virtual disk files to grow as the guest writes data, up to the configured maximum. This uses less host space initially, but the host volume must still be able to accommodate future growth.

For a data-heavy lab VM receiving repeated large transfers, immediate allocation can be useful when the host has sufficient free capacity. For a lightly used or growing lab disk, a dynamically growing disk can avoid reserving unused space immediately.

Choose the virtual disk file layout

Store the virtual disk as a single file: Keeps the virtual disk in one large host file. Choose this when the host filesystem supports the required file size. A single file can simplify some copying and management tasks.

Split the virtual disk into multiple files: Stores the disk across several host files. This is useful when the host filesystem has file-size restrictions or when portability to such a filesystem matters.

Older filesystems, including older FAT or ext variants, could impose file-size limits of approximately 2 GB. In those environments, a split disk may be necessary because one large virtual disk file cannot be created or copied there. On a modern host filesystem that supports the required size, a single-file disk is generally appropriate.

Name and store the virtual disk

  1. Choose the virtual disk filename and host-side location.
  2. Use a clear name that identifies the VM and purpose, such as a name indicating that the disk is a data or lab disk.
  3. Confirm that the destination has enough free space for the chosen allocation method and possible future growth.
  4. Consider the location's storage performance, backup coverage, and portability. A slow or nearly full volume can affect the VM, while a location excluded from backups can leave the new disk unprotected.

The virtual disk file location is part of the VM's storage design. If you move the file later, VMware must be able to locate it and the destination must preserve sufficient capacity and access permissions.

Finish and validate the attachment

  1. Review the wizard settings and select Finish.
  2. Verify that the new hard disk appears in the VM's hardware list in Virtual Machine Settings.
  3. Start the virtual machine.
  4. In the guest operating system, confirm that an additional blank disk is detected.

At this point, the VMware-side operation is complete, but the disk is not yet ready for ordinary file storage.

Prepare the disk inside the guest operating system

Guest-side preparation is analogous to preparing a newly installed physical disk. Keep it separate from creating the virtual disk file on the host.

  1. Detect the disk: Open the guest's disk management or storage utility and identify the new device by its size. Take care not to select an existing disk containing important data.
  2. Initialize it if required: Some guest operating systems require a new disk to be initialized before it can receive partitions.
  3. Create a partition or volume: Allocate all or part of the blank disk. You can create one region or multiple regions according to the guest workload.
  4. Format the partition or volume: Select a filesystem supported by the guest operating system and the intended use.
  5. Assign access: On systems using drive letters, assign a drive letter. On systems using mount points, attach the filesystem at a mount point.

After these steps, the guest should be able to create and read files on the new storage.

Practical examples

Data-heavy lab virtual machine

  1. Add a new SCSI hard disk to the existing VM.
  2. Choose capacity based on the expected dataset and future growth.
  3. Select immediate allocation when the guest will repeatedly receive large data transfers and the host has enough free capacity.
  4. Start the VM, then initialize, partition, and format the disk in the guest.

Host filesystem with file-size constraints

Create the new disk with the split-disk option. Splitting allows the virtual disk to be represented by multiple host files when the destination filesystem cannot store one large file.

General-purpose secondary data disk

Select the VM, open Player > Manage > Virtual Machine Settings, add a Hard Disk, create a new SCSI disk, select a suitable location, finish the wizard, and prepare the disk using the guest's storage management tools.

Troubleshooting

Add or hardware settings are unavailable

  • The VM may still be running or in a state that does not permit hardware changes. Power it off and reopen Virtual Machine Settings.
  • Confirm that the correct VM is selected in the library.
  • Check that your user account has permission to modify the VM configuration and files.

The new disk does not appear in the guest

  • Verify that the disk appears in VMware's hardware list.
  • Restart the guest or rescan storage devices using its disk management tools.
  • Review whether the selected controller type is supported by the guest and compatible with the VM configuration.

The guest sees the disk but cannot save files

The disk may still be blank, uninitialized, unpartitioned, or unformatted. It may also lack a drive letter or mount point. Complete the guest-side preparation sequence before testing file storage.

The host runs out of storage

  • With preallocation, the host may not have had enough free capacity for the full configured size.
  • With a dynamically growing disk, guest writes may have expanded the disk until the host volume became full.
  • Free or add host storage, relocate the virtual disk where appropriate, and plan for the disk's maximum potential growth.

A single virtual disk file cannot be created or copied

The destination filesystem may impose a file-size limit. Use the split virtual disk option or choose a host filesystem that supports the required file size.

The controller has no available attachment capacity

Review existing devices and the historical limits: up to 4 IDE devices, 60 SCSI devices, or 120 SATA devices, with SATA organized as up to 4 controllers of 30 devices each. Use another supported controller configuration when appropriate.

Exam-relevant notes

  • A virtual hard disk is stored by the host but presented to the guest as a disk device.
  • A newly created disk is blank until the guest initializes, partitions, and formats it.
  • Adding a disk, enlarging an existing disk, and attaching an existing disk are separate operations.
  • Preallocation reserves all configured capacity immediately; non-preallocated storage grows as data is written.
  • Single-file and split-file layouts are mainly differentiated by host filesystem limits and portability requirements.
  • Controller compatibility must be considered even when a controller still has attachment capacity.

Review this virtual hard disk procedure whenever you need to add another secondary disk to a VMware Workstation Player VM.