A VMDK (Virtual Machine Disk) file is a virtual hard disk used by VMware virtualization software.

VMware virtualization software

VMDK files can contain multiple components, including a descriptor file, flat file, delta file, and RDM (Raw Device Mapping) VMDK file. Here's an overview of each component and a tool that can help you recover them:

1. VMDK Descriptor File: The descriptor file is a small text file that describes the characteristics of the virtual disk, such as its size, geometry, and location of the flat file. If the descriptor file is lost or corrupted, the virtual disk may become inaccessible.

Tool: VMware vSphere Storage vMotion can help recover a lost or corrupted descriptor file by migrating the virtual machine to a new datastore. During the migration process, the descriptor file is rebuilt.

2. VMDK Flat File: The flat file is the actual virtual disk data stored in the VMDK file. If the flat file is corrupted or deleted, the virtual machine may not start or may show data corruption errors.

Tool: VMware vSphere Storage vMotion can also recover a lost or corrupted flat file by migrating the virtual machine to a new datastore. However, this method can be time-consuming, especially for large virtual disks. Another option is to use data recovery software such as EaseUS Data Recovery or Disk Drill to recover the deleted or corrupted file.

3. VMDK Delta File: The delta file is a snapshot of changes made to the virtual disk since the last snapshot. Delta files are used in virtual machine snapshots and can become corrupted or lost if there is a problem with the snapshot process.

VMware vSphere Storage vMotion

Tool: VMware vSphere Storage vMotion can recover a lost or corrupted delta file by migrating the virtual machine to a new datastore. Alternatively, you can try using data recovery software to recover the delta file from a backup or snapshot.

4. RDM VMDK File: A Raw Device Mapping (RDM) VMDK file is a special type of virtual disk that allows a virtual machine to access a physical disk or SAN LUN directly. RDM files can become inaccessible if there is a problem with the mapping or if the underlying physical disk is damaged.

Tool: VMware vSphere Storage vMotion may be able to recover a lost or inaccessible RDM VMDK file by migrating the virtual machine to a new datastore. However, if the underlying physical disk is damaged, you may need to replace it and restore from a backup.

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