Norwich Data Recovery — No.1 RAID 0/1/5/10 Recovery Specialists

25+ years of RAID expertise for home users, SMEs, large enterprises and public-sector teams. We recover data from hardware & software RAID, NAS and rack servers across all major vendors and filesystems. Free diagnostic and clear options before any work begins.

RAID Levels & Environments We Recover

RAID 0, 1, 5, 6, 10, 50, 60, JBOD, SHR/SHR-2, X-RAID, BeyondRAID, ZFS RAID-Z(1/2/3) on:

• NAS: Synology, QNAP, Netgear ReadyNAS, WD, Buffalo, Asustor, TerraMaster, Thecus, Lenovo/Iomega, LaCie*, Drobo*, Promise, TrueNAS/iXsystems (*DAS/Hybrid included).

• Rack/Server: Dell EMC, HPE, Lenovo, Supermicro, IBM/Power, Cisco UCS, Fujitsu, Inspur, Huawei, QCT/Quanta, ASUS, Tyan, Intel (legacy).

• Host/OS stacks: mdadm/LVM, Windows Dynamic Disks/Storage Spaces, macOS/APFS, Btrfs, ext4/XFS/ZFS, NTFS/ReFS, VMFS/NFS/iSCSI.

Top 15 NAS Brands in the UK & Popular Models

(Commonly deployed; we support all variants.)

1. Synology — DS923+, DS1522+, DS224+, RS1221+/RS2421+

2. QNAP — TS-464/TS-453D, TVS-h674, TS-873A, TS-451D2

3. Netgear ReadyNAS — RN424/RN524X, 2304, 528X

4. Western Digital (WD) — My Cloud EX2 Ultra, PR4100, DL2100

5. Buffalo — TeraStation TS3410DN/5410DN, LinkStation LS220D

6. Asustor — AS6704T (Lockerstor 4), AS5304T (Nimbustor 4)

7. TerraMaster — F4-423, F5-422, T9-423

8. Lenovo/Iomega — ix2/ix4, PX4-300D/PX6-300D (legacy but common)

9. LaCie — 2big/6big/12big (RAID DAS used as NAS via host)

10. Drobo — 5N/5N2 (legacy—still widely in use)

11. Promise — VTrak/Pegasus R-series (often shared over network)

12. TrueNAS / iXsystems — Mini X+, R-series

13. NetApp SMB — FAS entry models used as NAS shares

14. Zyxel — NAS326, NAS542

15. Seagate — BlackArmor/Business Storage (legacy)

Top 15 RAID Rack/Server Platforms & Popular Models

1. Dell EMC PowerEdge — R650/R750/R760, R740xd

2. HPE ProLiant — DL360/ DL380 Gen10/Gen11, ML350

3. Lenovo ThinkSystem — SR630/SR650, ST550

4. Supermicro — 1U/2U Ultra & SuperStorage (e.g., 6029/2029, 6049)

5. Cisco UCS — C220/C240 M5/M6

6. Fujitsu PRIMERGY — RX2540/RX2530

7. IBM Power / Storwize (legacy environments) — SFF/SAS arrays

8. Inspur — NF5280M6/M7

9. Huawei — FusionServer Pro 2288/5288

10. QCT (Quanta) — D52B-1U/D52BQ-2U

11. ASUS Server — RS520/RS700 series

12. Tyan — Thunder/Transport 1U/2U

13. Promise VTrak — E-Class/J-Class

14. Areca — ARC-1883/ARC-1886 series (controller-centric deployments)

15. Adaptec by Microchip — SmartRAID 31xx/32xx based servers

Our Professional RAID Recovery Workflow (What Happens in the Lab)

1. Intake & Free Diagnostic

   • Capture controller/NAS metadata, disk order, enclosure model, logs, SMART.

   • Evidence-grade case notes if required (chain-of-custody available).

2. Imaging First — Never the Originals

   • Block-level, read-only imaging of each member using hardware imagers (head-map, timeout budgeting, ECC controls).

   • Faulty disks imaged with per-head/zone strategies; SSDs with read-retry/voltage stepping.

3. Virtual Array Reconstruction

   • Detect member order, start offsets, stripe size, parity rotation (RAID-5), dual parity (RAID-6), delays/skips, “write-hole” artefacts.

   • Build a virtual RAID from the cloned images—no writes to originals.

4. Filesystem & Data Layer

   • Repair/assemble NTFS, ReFS, ext4, XFS, Btrfs, ZFS, APFS, HFS+; validate superblocks, journals, snapshots, and volume groups (LVM/MD/Storage Spaces).

   • For NAS: handle mdadm arrays, Btrfs/ZFS pools, SHR/X-RAID/BeyondRAID translations.

5. Verification & Delivery

   • Hash verification (MD5/SHA-256), sample file testing, directory spot checks.

   • Secure return via encrypted drive or secure transfer.

Note: Overwritten data (e.g., long-running rebuilds, CCTV circular overwrite) is not recoverable by any lab. We target pre-overwrite regions, snapshots, journals and unaffected replicas.

Top 50 RAID/NAS Failures We Recover — With Technical Approach

Summary format: Issue → Diagnosis → Lab Recovery (on cloned members/virtual array).

1. Multiple drive failures (RAID-5/6) → SMART/scan, bad-map correlation → Clone all members; parity maths to reconstruct missing stripes; selective parity disable where corruption detected.

2. Rebuild failure mid-process → Controller logs, stripe drift → Use pre-rebuild clone; rebuild virtually with correct order/offsets; ignore contaminated post-rebuild writes.

3. Wrong disk order inserted → Entropy analysis across stripes → Brute-force order solver; validate by filesystem signatures/Checksums.

4. Foreign/initialised disk added → Metadata diff → Recreate array from metadata copies on remaining members; exclude re-initialised disk.

5. Parity drive failure (RAID-5) → XOR reconstruction → Parity regenerate missing member ranges; verify via FS.

6. Dual failure (RAID-6) → P/Q parity maths → Solve per-stripe with Reed-Solomon; mask unreadable sectors with erasure coding.

7. Write-hole / unclean shutdown → Mismatch map → Per-stripe majority voting; filesystem journal replay on assembled image.

8. Stale metadata across members → Superblock epoch compare → Use highest consistent epoch; force mount read-only on virtual.

9. Controller NVRAM loss → Missing params → Infer stripe/rotation from data; parity analysis to deduce chunk size and rotation.

10. Firmware bug (synced wrong size) → Compare LBA spans → Truncate/align virtual members to common LBA; rebuild FS.

11. SSD wear-out in RAID → SMART wear, UBER rise → Low-stress imaging with read-retry matrices; fill holes via parity and FS awareness.

12. Bad sectors across drives → Error heatmap → Head-map imaging; parity reconstruct only the affected stripes.

13. Latent sector errors during rebuild → Logs/SMART pending → Stop rebuild path; image clones; reconstruct virtually avoiding poisoned stripes.

14. Silent data corruption (bit-rot) → Checksum mismatch (Btrfs/ZFS/ReFS) → Prefer blocks with valid checksums; scrub equivalent copies/mirrors.

15. Degraded RAID running for months → Heavy remap → Prioritised imaging of failing member; quick parity regen to stabilise virtual set.

16. Accidental reinitialisation → Metadata wipe → Carve prior metadata copies (e.g., mdadm superblocks at various offsets); reconstruct from survivors.

17. Accidental array deletion in GUI → NAS logs/snapshots → Recover superblocks; rebuild md/LVM map; mount data volume read-only.

18. Hot-spare mis-assignment → Event logs → Undo logical promotion in virtual model; exclude spare from early epoch writes.

19. Foreign import to another controller → Parameter drift → Recompute geometry; avoid auto-initialise; virtualise with correct parameters.

20. Firmware downgrade/upgrade mismatch → Layout change → Use on-disk metadata epochs to pick consistent layout.

21. Battery/Cache failure (BBU/CacheVault) → Incomplete writes → Journal replay; parity reconcile at stripe boundaries.

22. Controller dead (Adaptec/LSI/Areca) → No init → Clone all members; emulate controller layout in software; recover FS.

23. NAS OS migration (e.g., Synology→QNAP) → Different md/LVM → Parse native mdadm/LVM maps; do not let new NAS “repair” members.

24. BeyondRAID (Drobo) virtualisation loss → Proprietary layout → Translate chunk/metadata scheme with known patterns; export files from virtualised mapping.

25. X-RAID/SHR expansion halted → Multiple sizes → Rebuild md stacks per-member; assemble Btrfs/ext4 on top; copy data.

26. Btrfs metadata corruption → Superblock triplet → Select best pair; tree-search for root; extract subvolumes/snapshots.

27. ZFS pool degraded → vdev missing → Import with zpool import -F-o readonly equivalent on virtual images; scrub; zdb-assisted file export.

28. iSCSI LUN lost on NAS → LUN file sparse damage → Carve from underlying FS; reconstruct VMFS/NTFS inside LUN.

29. Extents misalignment after expansion → FS won’t mount → Fix partition/LVM geometry; expand filesystem metadata on clone; mount RO.

30. Thin-provisioned LUN overrun → Zeroed areas → Combine snapshots; carve guest FS; recover highest-value data first.

31. SMR disks in RAID write stall → Cache pressure → Image slowly with long timeouts; parity rebuild impeded stripes.

32. Bit-locker/FileVault inside RAID → Encrypted volumes → Full LUN image; decrypt with valid keys; mount RO for export.

33. Boot volume corrupted on NAS → OS partitions → Rebuild data volume offline; ignore OS volume, copy data only.

34. NVRAM log replay loops → Controller bug → Build array in software; bypass hardware log; proceed with FS repair.

35. Foreign sector size mix (512/4K) → Refusal to mount → Normalise to 512e or 4Kn in virtual model; repair FS structures.

36. Wrong TLER/ERC drives in RAID → Timeouts → Image each member with tuned timeouts; reassemble virtually.

37. Dropped disk reinserted as “new” → Epoch drift → Exclude the late epoch disk; use majority epoch set.

38. SMART trip then sudden death → Minimal reads → Early clone with head prioritisation; parity reconstruct missing blocks.

39. Filesystem journal corruption after incident → Dirty flag → Manual journal replay tools; rebuild directory trees.

40. LVM PV missing → VG won’t activate → Create virtual missing PV from parity; restore VG metadata; export LV data.

41. Storage Spaces unhealthy → Parity/columns unknown → Infer column/interop; assemble virtual pool; chkdsk-equivalent on clone.

42. VMFS header damage → ESXi can’t mount → Rebuild VMFS from copies; recover VMDK chain; present as files.

43. Hyper-converged (vSAN/ceph) member loss → Object map → Export objects from remaining replicas; rebuild VMs from components.

44. QNAP QuTS hero (ZFS) pool issues → TXG selection → Import with rewind; export datasets; avoid in-place fixes.

45. Synology Btrfs checksum errors → Scrub on images → Copy good extents first; reconstruct subvols.

46. Netgear X-RAID metadata split → Proprietary growth → Use known map; stitch volumes; copy data.

47. Controller-managed encryption enabled → Key store needed → If keys present, unlock virtual; else recovery limited to pre-encryption copies.

48. RAID 0 stripe member dead → No parity → Maximum raw imaging then file carving across surviving stripes; partial recoveries possible.

49. JBOD single member failure → Linear concat → Identify segment map; image intact members; carve across boundaries.

50. Overwritten by long rebuild/sync → Confirm overwrite → Focus on snapshots/backups/replicas and non-impacted systems; explain finite limits.

Top 20 Virtualised/“Virtual RAID” & VM Storage Problems — With Recovery Path

1. VMFS datastore corruption → Heuristic header rebuild; recover VMDK chain from flat/descriptor; mounter export.

2. VMDK snapshot chain broken → Re-stitch via CID/parentCID; where missing, binary diff alignment; mount final state.

3. Hyper-V AVHDX merge aborted → Reattach parent; replay log; export consistent VHDX.

4. Thin-provisioned LUN exhaustion → Zero holes in guest FS; snapshot-first copy; carve intact files.

5. iSCSI timeouts → NTFS corruption in guest → Stabilise LUN; chkdsk-equivalent on clone; MFT repair.

6. vSAN object/component loss → Export surviving components; reconstruct objects by policy (FTT); rebuild VMs.

7. Ceph/Gluster heal incomplete → Copy from healthy replicas; avoid self-heal until data exported.

8. Storage vMotion interrupted → Partial migration → Recover both source/target; choose newest intact chain.

9. VM encryption (vSphere/Windows/Linux) → Requires keys; decrypt cloned images; export.

10. LVM inside VM damaged → Rebuild PV/VG/LV maps; mount filesystems.

11. APFS containers inside VMDK → Walk checkpoints; mount RO; copy.

12. ReFS inside VHDX → Object table recovery; handle block clone.

13. Extents misalignment in guest → Fix partition table; restore superblocks; mount.

14. Orphaned NFS datastore → Manually mount export; copy VMDKs; rebuild registrations.

15. SR-IOV/virt-cache write loss → Journal repair in guest; verify DB integrity.

16. Backup proxy corruption (Veeam/etc.) → Restore from intact VBK/VIB chains; or carve from temporary LUNs.

17. Snapshots auto-deleted by quotas → Use underlying FS snapshots (ZFS/Btrfs/VSS) to roll back; export files/VMs.

18. Guest DB crash-consistency only → Log replay (SQL/Oracle/Postgres); verify app-level checks.

19. Split-brain after failover → Choose authoritative side by epoch; copy off; reconcile later.

20. Controller cache write-back lost → Filesystem log replay; parity reconcile on virtual array.

Why Choose Norwich Data Recovery

• 25 years in business; thousands of successful RAID/NAS recoveries

• Multi-vendor expertise across controllers, NAS OSs, filesystems and VM stacks

• Advanced toolchain & donor inventory to maximise success

• Free diagnostic with clear, no-surprise options before work begins

Speak to an Engineer

Contact Norwich Data Recovery today for your free diagnostic. We’ll stabilise your array, rebuild it virtually and get your data back—safely, quickly, and with full technical transparency.