> For the complete documentation index, see [llms.txt](https://docs.parallels.com/landing/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.parallels.com/landing/parallels-desktop-developers-guide/command-line-interface-utility/manage-virtual-machines-from-cli/virtual-machine-configuration-tasks/device-management/virtual-hard-drive.md).

# Virtual Hard Drive

### Adding a Hard Drive

**--device-add hdd** \[**--image** <*image\_name*>] \[**--type** <**expand** | **plain**>] \[**--size** <*n*>] \[**--split**]

\[**--iface** <**ide** | **scsi** | **sata**>] \[**--position** <*n*>]

\[**--subtype** <**buslogic** | **lsi-spi** | **lsi-sas**>]

\[**--online-compact** <**on** | **off**>]

### Modify a Hard Drive

**--device-set** <*hdd\_name*> \[**--image** <*image\_name*>] \[**--type** <**expand** | **plain**>]

\[**--size** <*n*>] \[**--split**] \[**--iface** <**ide** | **scsi** | **sata**>] \[**--position** <*n*>]

\[**--subtype** <**buslogic** | **lsi-spi** | **lsi-sas**>] \[**--online-compact** <**on** | **off**>]

#### Parameters

*hdd\_name:* The name of the virtual hard drive to modify (-**-device-set** command only). Virtual hard drives are named using the hddN format, where N is the drive index number starting from 0 (e.g., hdd0, hdd1). To obtain the list of disk names, use the `prlctl list --info` command.

**--image**: specifies the name of the file to be used for emulating the VM virtual disk drive. If this option is omitted, a new file is created inside the directory storing all VM-related configuration files and assigned the name of `harddiskN.hdd`.

**--type**: specifies the type of the virtual disk from one of the following:

* **expand (default)**: virtual disks of this type are small initially and grow in size as you add data to it.
* **plain**: virtual disks of this type have a fixed size from the moment of their creation.

**--size**: hard disk size, in megabytes.

**--split**: splits the hard disk into 2GB pieces.

**--iface**: virtual hard disk interface type: **ide**, **scsi**, or **sata**.

**--position**: the SCSI / IDE / SATA device identifier to be used for the disk drive. Allowed ranges:

* 0-3 for IDE disk drives
* 0-6 for SCSI disk drives
* 0-5 for SATA disk drives

**--subtype**: virtual hard disk subtype: **buslogic**, **lsi-spi**, **lsi-sas**.

**--online-compact**: enables or disables virtual hard disk online compact mode.


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