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Backup Engine

Block-level. Deduped. Incremental forever.

VSS snapshot, NTFS bitmap walk, content-defined deduplication. The backup engine grows incrementally and never bloats. Multi-volume support for system + recovery + data partitions.

Block-level imaging in BigMind — VSS snapshot, NTFS bitmap walk, content-defined dedupClick to enlarge
~30-60 min
Initial full backup
typical 100GB Windows, network-bound
30 sec–5 min
Incremental backup
block-level scan + dedup
0M+
Files per device
no performance degradation
0
Synthetic fulls
required, ever

How it works

How block-level imaging works

Four steps, every backup. The engine quiesces the OS, reads only the blocks that hold data, dedupes them against everything you’ve ever stored, encrypts, and writes to a content-addressed store.

VSS Snapshot
quiesce + freeze
NTFS Bitmap
walk allocated blocks
Dedup
content-defined
Encrypt
per-chunk
Store
content-addressed

VSS Snapshot → NTFS Bitmap → Dedup → Encrypt → Store — the same pipeline runs on every backup.

Inside the engine

Three techniques, one consistent image.

VSS Snapshot

Quiesce the OS and freeze writers, then take a moment-in-time snapshot — a consistent image of a live, running machine. No torn files, no half-written databases.

NTFS Bitmap Walk

Read the NTFS allocation bitmap to capture only the blocks that hold data, skipping empty regions — so a sparse 1 TB drive only reads what is actually used.

Content-Defined Dedup

Identical chunks across every backup are stored once in a content-addressed store. No “synthetic full” ever — the manifest references chunks directly and grows by delta only, so the chain never gets more fragile.

Multi-Volume

Bootable, not just copied.

Modern Windows installs span 4+ partitions: System Reserved (1MB), MSR (16MB), recovery (~500MB), and main C:. We image all of them together — so a restore puts the machine back to bootable, not just “the C: drive copied.”

  • System Reserved + MSR + recovery + C: — captured in one image
  • Restores to a bootable machine, not a bare data copy
  • 10M+ files per device with no performance degradation
Multi-volume recovery in BigMind Recovery ShieldClick to enlarge

Block-level. Forever incremental.

VSS snapshot, NTFS bitmap walk, content-defined dedup — the backup engine that grows by delta only and never bloats.