Deduplicated Storage: Rebuild the Mapping Before the Data
A deduplicated volume is not a filesystem you can scan: identical blocks are stored once and referenced many times.
Why scanning fails
File contents are fragmented into references. Without the mapping tree, signature scanning finds the block but cannot attribute it to a file, path, or offset.
Correct order
Image all members, rebuild the reference map from metadata databases, then reconstruct files by walking references. Never run fsck-style repairs on the underlying layer first.
FAQ
Is recovery possible if the map is gone?
Only partially — some appliances keep journals or checkpoints that can be replayed.
Does compression change the order?
It must be undone before file reconstruction.