When a snapshot is taken in VMware, the original base disk becomes read-only, and a new delta file is created to capture subsequent writes.
: The actual data blocks changed since the last snapshot. Method 1: Standard Restoration via vSphere Client restore vmware from delta vmdk
Delta files are dependent on their parent disks. You cannot simply move a delta file to another VM and power it on; the parent CID (Content ID) and chain must remain intact. When a snapshot is taken in VMware, the
| Error Message | Cause | Resolution | | :--- | :--- | :--- | | | CID mismatch between parent and child. | Edit descriptor files to align CID values (Method C). | | "Disk is locked" | The VM still has a lock on the file, or a backup software is holding it. | Kill processes holding the lock via lsof | grep VM_Name in SSH, or migrate the VM to another host. | | "File not found" | Descriptor file text points to wrong flat/delta file name. | Check the RW line in descriptor: RW 83886080 VMFS "VM_Name-000002-delta.vmdk" . Ensure filename is exact. | You cannot simply move a delta file to
She couldn’t skip it. The VM would boot but corrupt data silently.
Maria documented everything and added a new rule: No snapshot older than 72 hours without a consolidation plan. She also wrote an internal tool called delta-forensics to map block dependencies across a chain.