VMDK to VHD Converter

About This Tool

This tool performs offline conversion of a VMDK disk image into the VHD format, enabling cross-platform virtualization workflows for IT admins and virtualization engineers. It reads the source VMDK, preserves disk geometry, partitions, and metadata, and writes a standards-compliant VHD file suitable for Hyper-V and other VHD consumers. The operation is deterministic and does not modify the original source, minimizing risk during migration planning, testing, and DR readiness.

Conceptually, the converter treats the source image as a sequence of blocks and rebuilds its contents into a VHD container, aligning blocks to the VHD schema and preserving sparse regions where supported. It supports both fixed-size and dynamically expanding VHDs, with chunked processing to handle large disks without excessive memory usage. The tool performs integrity checks optionally and produces a concise log of mapping decisions, encountered warnings, and verification results. This design enables predictable outcomes in production environments.

Inputs & Outputs: Inputs include: source_file (file upload, required), source_format (enum, default VMDK, constrained to VMDK), target_format (enum, required, VHD), options (object with booleans for fixed_size, preserve_sparse, verify_checksum). Outputs include: output_file (VHD file, size in bytes, creation timestamp), logs (text), and optional metadata bundle. The tool uses a block-level mapping algorithm to transpose VMDK blocks to VHD blocks, preserving sector alignment and sparse regions where supported. It does not perform data recovery; it only repackages existing contents. Validation involves optional digest computation and cross-checksums against copied blocks. The tool handles missing inputs with explicit errors, unsupported source/target formats, corrupted source images, and disk-size limits. Large VMDK files are processed in chunks; partial failures emit an actionable log without corrupting the destination. Uses standard disk-size units (bytes, KiB, MiB, GiB) and adheres to VMware VMDK and Microsoft VHD specifications. Assumes source VMDK is accessible, unencrypted, and not a live-running disk; Excludes in-place repair or multi-disk span consolidation.

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