Southampton Data Recovery are the UK’s No.1 RAID 5, RAID 6 and RAID 10 recovery specialists. If your parity or mirrored-stripe array is degraded, partially rebuilt, or completely offline—on a NAS, DAS, rack server or SAN shelf—our engineers provide free diagnostics, best-value options and 25+ years of enterprise-grade expertise across home users, SMEs, multinationals and government. We handle every platform and filesystem, including linux raid 5 recovery (mdadm/LVM), controller-based raid 5 recovery on Dell/HPE/Lenovo, and complex raid 10 data recovery with tiered SSD caches and snapshots. For search visibility, yes—we perform raid 5 data recovery, linux raid 5 recovery, raid 5 recovery, and raid 10 data recovery daily on Synology, QNAP, Netgear, Buffalo, LaCie, Promise, and more.

Platforms we routinely recover

Below are UK-common brands we see most often. Model lists are representative of “popular/commonly-deployed” devices we regularly encounter in-lab.

Top 15 NAS / external RAID brands in the UK (with popular models)

1. Synology – DS224+, DS423+, DS923+, DS1522+, RS1221+

2. QNAP – TS-262, TS-464, TS-453D, TVS-h874, TS-873A

3. Western Digital (WD) – My Cloud EX2 Ultra, PR2100/PR4100, My Cloud Home Duo

4. Netgear ReadyNAS – RN212, RN424, RR3312/RR4312 (rack)

5. Buffalo – LinkStation LS220D, TeraStation TS3420DN/TS5400DN

6. Asustor – AS1102T, AS5304T (Nimbustor 4), AS6604T (Lockerstor 4)

7. TerraMaster – F2-423, F4-423, F5-422, D5-300C (external RAID)

8. LaCie (Seagate) – 2big/5big/6big RAID (USB-C/TB DAS)

9. Promise Technology – Pegasus R4/R6/R8 (TB DAS), VTrak D5000 series

10. Drobo – 5N/5N2, 5D/5D3, 8D (BeyondRAID; still in UK estates)

11. Thecus – N2810/N4810/N5810PRO, rack N7710

12. TrueNAS (iXsystems) – TrueNAS Mini X, X-Series (ZFS RAID-Z mirrors/RAID10-like)

13. Lenovo/Iomega – ix2-DL, ix4-300d, px4-300d (legacy but common)

14. Zyxel – NAS326, NAS542

15. D-Link – DNS-327L, DNS-340L

Top 15 servers / storage commonly deployed with RAID 5 & RAID 10 (with popular models)

1. Dell PowerEdge / PowerVault – R650/R750/R740xd; PowerVault ME4012/ME4024

2. HPE ProLiant / MSA – DL360/DL380 Gen10/Gen11; MSA 2060/2062

3. Lenovo ThinkSystem / DE-Series – SR630/SR650; DE4000/DE6000

4. Supermicro SuperServer – 1U/2U storage chassis (1029/2029/6029/6049)

5. Cisco UCS C-Series – C220/C240 M5/M6 with Broadcom/LSI RAID

6. NetApp FAS/AFF – FAS2700, entry AFF A-series exporting LUNs

7. Synology RackStation – RS1221+, RS3621xs+, RS4021xs+

8. QNAP Enterprise (QuTS hero/ZFS) – ES2486dc, TS-h1886XU, TS-h2490FU

9. TrueNAS X/M (iXsystems) – X20/X30, M40/M50 (mirrored vdevs / striped mirrors)

10. Promise VTrak – E/D-Series (hardware RAID 5/6/10)

11. Fujitsu PRIMERGY – RX2540/RX1330 storage configs

12. ASUS RS-Series – RS720/RS520 (with Broadcom/Adaptec RAID)

13. Huawei OceanStor – 2200/2600 SMB deployments

14. Qsan / Infortrend – XCubeSAN/XCubeNAS; EonStor GS family

15. Netgear ReadyNAS Rackmount – RR3312/RR4312 (SMB clusters)

Why parity & mirrored-stripe arrays fail (and why lab recovery is essential)

• RAID 5 tolerates one failed member; RAID 6 tolerates two; RAID 10 tolerates one per mirror set (but not two in the same pair). A rebuild stresses the remaining disks; UREs (Unrecoverable Read Errors) and latent defects often appear during the rebuild and kill the process.

• Controllers and NAS stacks maintain on-disk metadata; OCE (Online Capacity Expansion), level migrations (5→6), cache/BBU faults, sector-size mismatches (512e/4Kn), HPA/DCO truncation, and firmware bugs can all introduce stripe incoherence and parity drift.

• Correct raid 5 data recovery / raid 10 data recovery requires: (1) stabilising each member (mechanical/electronic/firmware); (2) forensic cloning to lab targets; (3) deriving exact geometry (order, offsets, stripe size, parity rotation, sector size); (4) virtual array rebuild from the images only; (5) filesystem/LUN repair and verified extraction. For linux raid 5 recovery we additionally reconstruct md superblocks, LVM metadata and thin pools.

Top 30 RAID 5 & RAID 10 faults we recover (each with the exact in-lab fix)

Each item includes a plain-English summary and the technical lab process (software + electronic + mechanical). This reflects what we actually do on the benches.

1. UREs during RAID 5 rebuild
   Summary: Rebuild aborts because the surviving disks have hard read errors in parity stripes.
   Lab fix: Stabilise members; head-map imaging with ECC-aware retries and thermal cycles; create per-member defect maps; rebuild the array virtually from images; use parity math to re-synthesise unreadable blocks; then repair FS journal.

2. Second disk fails mid-rebuild (RAID 5) / two disks in same mirror (RAID 10)
   Summary: Rebuild begins, another member drops; array goes offline.
   Lab fix: Mechanical/electronic remediation (donor heads, PCB+ROM swap, translator repair) to obtain at least partial clones; reassemble virtually; for RAID 10, reconstruct per-mirror timelines, then stripe them.

3. Parity write-hole after power loss (5/6/10 with write-back cache)
   Summary: In-flight stripe writes leave parity/data out of sync.
   Lab fix: Work from clones; journal/log replay; parity reconciliation by targeted XOR of dirty regions identified from controller logs/bitmap (when available) and FS intent logs.

4. Controller/NVRAM failure—lost array metadata
   Summary: BIOS shows “foreign config” or wrong virtual disk geometry.
   Lab fix: Dump on-disk metadata; reverse-engineer stripe size, parity rotation (e.g., left-symmetric), member order and offsets; emulate controller in software; validate with FS signatures; mount read-only.

5. Disk order changed after maintenance
   Summary: Members reinserted in wrong slots; parity maths no longer align.
   Lab fix: Stripe-signature analysis across members to derive the exact order/rotation; confirm with parity consistency checks; rebuild virtually.

6. OCE (Online Capacity Expansion) failed mid-operation
   Summary: Expansion interrupted by crash or UREs; array won’t mount.
   Lab fix: Recover pre- and post-OCE layouts from superblocks and controller journals; mount both virtually; merge extents; repair FS.

7. Level migration failed (RAID 5→6 or 10 reshape)
   Summary: Migration/reshape aborted; metadata inconsistent.
   Lab fix: Decode migration markers; reproduce controller algorithm in software; finish migration virtually; validate FS integrity.

8. Mixed sector sizes (512e vs 4Kn) across members
   Summary: Replacement drive uses different logical sector size; subtle misalignment corrupts parity.
   Lab fix: Clone to normalised sector-size targets; apply per-member offset correction; reconstruct with canonical sector size.

9. HPA/DCO hidden capacity causes stripe truncation
   Summary: One member reports fewer LBAs; end-of-array stripes differ.
   Lab fix: Detect/remove HPA/DCO (on images or safe clones); normalise capacity; rebuild; verify end-stripe parity before FS work.

10. Backplane/SAS expander link resets
    Summary: CRC storms/link drops cause silent corruption and drive fall-outs.
    Lab fix: Bypass expander; direct-attach via clean HBA; image each drive; reconstruct array off-box; post-recovery recommend backplane replacement.

11. Firmware BSY lock / microcode anomalies (disk level)
    Summary: Drive stays busy, won’t ID; array degrades.
    Lab fix: Vendor terminal BSY clear, module reload, ROM transplant if required; conservative cloning; integrate image into virtual rebuild.

12. Translator corruption / slow SA (disk level)
    Summary: 0-LBA, extremely slow reads due to SA module damage.
    Lab fix: Regenerate translator; disable background scans; head-select imaging; parity math to fill unavoidable holes.

13. Head crash / media damage on a member
    Summary: Clicking, rapid failure; parity set incomplete.
    Lab fix: Clean-room head stack swap (matched donor by micro-jog/P-list); calibrate; multi-pass imaging (outer→inner, skip windows, return later); rebuild parity set virtually.

14. PCB/TVS failure after surge
    Summary: No spin/detect on one or more members.
    Lab fix: Donor PCB with ROM/NVRAM transfer; TVS/fuse rework; verify preamp current; clone, then parity rebuild.

15. Motor seizure/stiction
    Summary: Spindle locked; member unavailable.
    Lab fix: Platter transfer or motor transplant; servo alignment; low-stress cloning; integrate partial/complete image into reconstruction.

16. Cache/BBU failure (controller cache battery/capacitor)
    Summary: Cache switches to write-through or corrupts writes.
    Lab fix: Disable cache; reconcile parity inconsistencies during virtual rebuild; journal-guided FS repair; post-recovery replace BBU/cache.

17. RAID 10 mirror pair divergence
    Summary: One mirror holds newer data; the other holds older consistent data.
    Lab fix: Build per-pair version maps; prefer consistent timelines to avoid poisoning; then stripe the chosen mirror images; verify with FS checks.

18. mdadm reshape/expand interrupted (Linux)
    Summary: --grow/reshape stopped; array unmountable.
    Lab fix: linux raid 5 recovery: parse md superblocks, locate reshape position and new geometry; finish reshape in software; validate LVM/thin metadata; mount.

19. mdadm assemble forced with wrong order/role
    Summary: Manual assemble --force writes bad superblocks.
    Lab fix: Take forensic images of all members; roll back to pre-change metadata on the images; derive true order/role; reassemble read-only; copy-out.

20. LVM thin-pool metadata corruption on top of RAID
    Summary: LVs go read-only/missing; pool won’t activate.
    Lab fix: Restore thin-pool metadata from spare area/snapshots; manual LV mapping; mount filesystems read-only; export.

21. VMFS/VMDK datastore corruption (ESXi on RAID 5/10)
    Summary: VMFS invalid; VMs won’t boot.
    Lab fix: Rebuild RAID virtually; parse VMFS; repair VMDK descriptors & extents; restore VMs to clean storage.

22. Btrfs RAID5/6 chunk map inconsistencies
    Summary: Btrfs volume mounts degraded/readonly; scrub loops.
    Lab fix: Clone first; btrfs-rescue & chunk map rebuild; copy-out by checksum-verified reads; advise migration to stable layout.

23. ZFS pool with missing/detached vdevs (striped mirrors)
    Summary: Pool unimportable or degraded.
    Lab fix: Clone members; zpool import -F -o readonly -R <altroot>; use zdb to examine uberblocks; recover latest consistent TXG; export datasets/snapshots.

24. Synology SHR (RAID5/RAID6-like) metadata loss
    Summary: SHR won’t assemble; volume missing.
    Lab fix: Reassemble md layers; reconstruct SHR mapping; mount EXT4/Btrfs read-only; checksum-verified extraction.

25. QNAP QuTS hero (ZFS) import fails
    Summary: QNAP ZFS pool refuses import after update/fault.
    Lab fix: Clone; zpool import with compatibility flags & readonly; export via send/receive or direct copy; rebuild new pool if needed.

26. iSCSI target database corruption (NAS)
    Summary: LUNs disappear though backing storage intact.
    Lab fix: Rebuild target DB from config fragments; attach LUN backings read-only; recover VMFS/NTFS inside.

27. Snapshot reserve exhaustion → metadata collapse
    Summary: NAS snapshots fill the pool; writes stall; volume corrupts.
    Lab fix: Mount base volumes from clones; roll back to last consistent snapshot by object map; export data; advise snapshot policy changes.

28. Dedup store/index damage
    Summary: Deduplicated blocks lose references; files vanish.
    Lab fix: Rebuild dedup tables from logs; export unique blocks to a fresh, non-dedup target; rehydrate logical files.

29. Time skew / NTP rollback in clusters
    Summary: Journals conflict; nodes write out-of-order.
    Lab fix: Choose the most consistent node image; export that snapshot; reconcile application data (DB/VM) from logs to latest safe point.

30. Human error: wrong disk cloned/replaced during outage
    Summary: A new clone overwrites a good member; parity now wrong.
    Lab fix: Attempt rollback via residual analysis on overwritten disk (limited); otherwise reconstruct from remaining members + parity; heavy FS carve for partial salvage.

Our end-to-end recovery workflow (what we actually do)

1) Forensic intake & stabilisation

• Log controller/NVRAM config, slot order, SMART, PSU quality; quarantine enclosure/backplane faults.

• Electronics: TVS/fuse checks, donor PCB with ROM/NVRAM transplant; firmware (translator/defect lists).

• Mechanics: head swaps, motor/platter work, SA module repair.

• We never power-cycle weak disks repeatedly.

2) Imaging—always first, always read-only

• Adaptive, head-select imaging with ECC-aware retries, timeout tuning, zone cooling; per-member defect maps.

• SSD/NVMe: vendor toolbox unlock; if needed, chip-off NAND and LBA map rebuild.

• Originals are preserved; all work is done from verified images.

3) Virtual array reconstruction

• Derive level, stripe size, parity rotation, start offsets, member order, sector size, HPA/DCO.

• Emulate the original controller; reconcile parity drift/write-hole regions.

• Validate with FS signatures, entropy checks and parity consistency scans.

4) Filesystem/LUN repair & extraction

• Read-only mount of NTFS, EXT4, XFS, Btrfs, ZFS, APFS, HFS+, ReFS, VMFS.

• Journal/log replay or manual metadata surgery (MFT mirror, alt-superblocks, XFS phased repair).

• Export to clean media with hash verification (per-file/per-image) and optional recovery report.

5) Hardening & advice

• Replace suspect disks in sets; standardise 512e/4Kn; verify UPS/BBU; schedule scrubs; establish snapshot & backup policy (RAID ≠ backup).

• For performance with resilience, prefer RAID 10 (striped mirrors) to minimise URE-induced rebuild failures seen in RAID 5.

Why Southampton & Norwich Data Recovery?

• 25+ years specialising in raid 5 data recovery, linux raid 5 recovery, raid 5 recovery, and raid 10 data recovery.

• Full-stack capability: mechanical, electronic, firmware and filesystem.

• Advanced tools & parts inventory (donor heads/PCBs, ROM programmers, SAS/SATA/NVMe HBAs, expander-bypass kits, enclosure spares).

• Safe methodology: clone first, emulate/assemble virtually, mount read-only.

What to do now

1. Power down—don’t retry rebuilds or swap disks blind.

2. Label each drive in order; pack in anti-static sleeves inside a padded box.

3. Contact our Southampton RAID engineers for free diagnostics—UK-wide courier or local drop-in available the same day.

Southampton Data Recovery – Contact our RAID 5, RAID 6 and RAID 10 specialists today for a free diagnostics.