How To Fix Flat Vmdk [exclusive] May 2026

1. Overview A flat VMDK is a raw, pre-allocated virtual disk file containing all the guest OS data in a monolithic, binary format (typically named vmname-flat.vmdk ). It is always paired with a small descriptor file ( vmname.vmdk ) containing geometry and metadata.

2025-03 Applicable VMware versions: ESXi 6.x, 7.x, 8.x how to fix flat vmdk

vmkfstools -i broken-flat.vmdk repaired.vmdk -d thin This reconstructs metadata and skips unreadable sectors (best-effort). Mount the raw flat file as a loop device on Linux: 2025-03 Applicable VMware versions: ESXi 6

# Calculate offset (for MBR partition table, first partition starts at sector 2048) losetup -f --show -r vmname-flat.vmdk kpartx -av /dev/loop0 mount /dev/mapper/loop0p1 /mnt/recovery 2025-03 Applicable VMware versions: ESXi 6.x

# Find all descriptor files find /vmfs/volumes/datastore/ -name "*.vmdk" -type f vmkfstools -z /path/to/orphaned-flat.vmdk /new/path/fixed.vmdk 3.4 Repair After VMFS Metadata Corruption Use vmkfstools to clone the flat VMDK to a new healthy one: