Deduplication, compression, incremental scope, encryption and WORM are different features. Visible options or PoC/development acceptance do not establish production readiness on every platform or fixed savings.
Screenshots were captured from the actual lab interface on 16 October 2026. The interface is in English; explanations follow your selected language. Resource names, dates and settings are examples; use values for your own environment.
Visual/action limit: the earlier real VM Advanced Settings image is reused unchanged; visible options are not runtime acceptance. No new Agent/backend measurement screen was captured. No dedup/compression setting, filesystem maintenance, chunk deletion or backup/restore was performed.
Platform, engine, backend and release identity
Representative data, Full/incremental and measurement layer
CPU/I/O/network cost and physical capacity
Hash and isolated-restore acceptance
01
1. Identify the deduplication layer
Backup-engine/repository chunk sharing, source Windows deduplicated-volume optimization and BTRFS extent dedup are different mechanisms. Record platform, method, backend and installed release. dd_dedup_poc is a proof of concept, not evidence of general production support or Data Domain equivalence.
Expected result
Layer, data scope and measurement results are recorded.
02
2. Prepare representative data and baseline measurements
Record a small representative dataset with repeated/changing blocks, logical bytes, physical usage, transferred bytes and duration. Compressed/encrypted data and zero blocks affect results. Compare ratios only with matching datasets, Full/incremental methods and measurement layers.
Expected result
Layer, data scope and measurement results are recorded.
03
3. Check the actual scope of policy options
Distinguish VM Advanced Settings → Enable deduplicated volumes from agent Deduplication for File Backup and Enable optimized backup of windows deduplicated volumes. Fields may be hidden by source/method. A visible option does not establish global repository dedup for every platform; validate the installed backend and supported scope.
Earlier real VM Policy Advanced Settings screen: policy options including High Compression/deduplicated-volume fields. This is an unsaved lab draft, not proof of engine application, codec or savings ratio. Enlarge ↗
Expected result
Layer, data scope and measurement results are recorded.
04
4. Assess repository chains and chunk sharing
The RustFS native design describes content-addressed chunk sharing and reuse of unchanged chunks across Full/incremental backups; manifest integrity needs separate verification. Development round-trip acceptance does not clear all production gates. Never manually delete referenced chunks; assess retention/GC and encryption/dedup scope against the backend release.
Expected result
Layer, data scope and measurement results are recorded.
05
5. Keep BTRFS maintenance separate from backup
The BTRFS runbook’s erabackup_btrfs_dedup.py does not take backups; report, dry-run, dedup and verify are separate modes. Actual dedup can change extent sharing through duperemove; it is not a policy checkbox or read-only report. Do not run it in production without validating mounts, maintenance windows and restore acceptance.
Expected result
Layer, data scope and measurement results are recorded.
06
6. Measure ratios and resource cost together
Identify whether metrics represent logical, unique, physical or transferred bytes. Do not double-count transfer reduction, incremental scope and compression in the same saving ratio. Compare CPU, memory, I/O, duration and reservations; one lab result does not guarantee fixed savings or speed.
Expected result
Layer, data scope and measurement results are recorded.
07
7. Accept through Full/incremental restore
In an approved small test, create Full and changed-data incremental points and compare hashes/application acceptance after isolated restore. Include the oldest required chain and post-cleanup references in the test plan. This inspection enabled no dedup, ran no BTRFS maintenance and produced no backup/restore.
Expected result
Layer, data scope and measurement results are recorded.
COMMON QUESTIONS
Is there a fixed savings or speed ratio?
No. Measure against data, method, layer and resource cost; separately accept hashes/data and isolated restore.