RAID 10 Data Recovery Services
RAID 10 combines mirroring and striping to deliver both redundancy and throughput. When a mirror pair fails or a controller loses its metadata, the array goes offline and standard tools cannot read it. We image each member drive through write-blocked channels, reconstruct the stripe-of-mirrors layout from cloned data, and extract your files without writing to the originals. Our RAID data recovery service covers all array levels; this page focuses on RAID 10 specifically. Free evaluation. No data = no charge.
How Does RAID 10 Combine Mirroring and Striping?
RAID 10 is a nested array that mirrors data within drive pairs first, then stripes those pairs together. This gives read/write performance close to RAID 0 with the redundancy of RAID 1 at the cost of 50% usable capacity.
- In a 4-drive RAID 10, drives are grouped into two mirror pairs. Drive A1 and A2 hold identical data (mirror pair A). Drive B1 and B2 hold identical data (mirror pair B). Incoming writes are split into stripes and distributed across mirror pair A and mirror pair B.
- A 6-drive RAID 10 has three mirror pairs; a 12-drive RAID 10 has six. Each pair operates as an independent RAID 1 within the larger striped set. The controller reads from whichever mirror member responds faster, which doubles read throughput.
- Enterprise deployments commonly run RAID 10 across 8, 12, 16, or 24 drives for database servers (SQL Server, Oracle, PostgreSQL), virtualization hosts (VMware ESXi, Hyper-V), and any workload that demands high IOPS with fault tolerance.
- RAID 10 differs from RAID 01 in construction order. RAID 01 stripes first and then mirrors the stripe sets. This distinction matters for fault tolerance: in RAID 01, a single drive failure degrades an entire stripe set, and any subsequent failure in the surviving stripe set causes total loss. In RAID 10, a single failure only degrades one mirror pair, and the array survives as long as every pair retains at least one healthy member.
When Does a RAID 10 Array Become Unrecoverable?
A RAID 10 array fails when both drives in any single mirror pair are lost. The critical factor is which drives failed relative to the mirror pairs, not the total number of failures.
- Two drives failing in different mirror pairs: the array continues operating in a degraded state. Each affected pair still has one surviving member. No data is lost.
- Two drives failing in the same mirror pair: that span's data is gone from the stripe set. The controller takes the volume offline. Without at least one readable copy from every mirror pair, the full dataset cannot be assembled.
- Recovery in the second scenario depends on whether we can restore at least one drive in the failed pair. If a drive failed due to a burned TVS diode, a seized motor, or corrupted firmware, physical intervention (board repair, head swap, PC-3000 firmware reconstruction) can bring it back to a readable state. Once one member per pair is imaging, the array can be reconstructed.
- Controllers like Dell PERC H730/H740/H755, HP Smart Array P408i/P816i, and LSI MegaRAID store RAID metadata in proprietary formats on the drives and in controller NVRAM. If the controller itself dies, or if the array was imported to a replacement controller that altered the metadata, recovery requires reverse-engineering the original stripe configuration from the raw drive images.
- Degraded RAID 10 arrays left running while a rebuild proceeds are at peak risk. If a second drive in the same mirror pair fails during the rebuild (common with aging drives under heavy I/O), the array drops offline. Power down a degraded array and contact a recovery service before initiating a rebuild on questionable hardware.
Do not rebuild: Forcing a RAID rebuild on aging drives under heavy I/O often triggers a second failure in the same mirror pair. Power down and preserve the current state.
Our RAID 10 Recovery Process
We recover RAID 10 arrays by imaging every member through write-blocked hardware, identifying the mirror pair assignments and stripe layout, and reconstructing the virtual array offline from cloned images.
- Free evaluation and intake: Document the array configuration: member count, controller model (Dell PERC, HP Smart Array, LSI MegaRAID, software mdadm), RAID level confirmation, stripe size, and slot positions. Drives are labeled with their original bay numbers.
- Write-blocked forensic imaging: Each member drive is cloned individually using PC-3000 and DeepSpar hardware with conservative retry settings and head-map optimization. For a 12-drive RAID 10, this means 12 sequential imaging sessions. No writes touch the original drives.
- Physical intervention (when needed): Members with mechanical failures (clicking, seized motor, head crash) receive donor head transplants or motor repair on a Purair VLF-48 laminar-flow bench before imaging. Electrically damaged PCBs are diagnosed and repaired at the component level under microscope.
- Controller metadata analysis: Proprietary RAID metadata from the controller is extracted from member drive reserved areas. For hardware controllers like Dell PERC H755 or HP P816i, the metadata encodes mirror pair assignments, stripe block size, and member ordering. When the original controller is unavailable, we reverse-engineer these parameters from the raw data layout across member images.
- Offline array reconstruction: PC-3000 RAID Edition assembles the virtual RAID 10 from cloned images. Mirror pairs are mapped, the stripe interleave is validated against known filesystem structures, and parity across pairs is cross-checked. The reconstructed volume is mounted read-only.
- Filesystem extraction and delivery: R-Studio or UFS Explorer extracts files from the reconstructed volume (NTFS, EXT4, XFS, ZFS, VMFS). Priority data such as database files, virtual machine images, and shared folders are verified first. Recovered data is delivered on your target media and all working copies are purged on request.
How Much Does RAID 10 Recovery Cost?
RAID 10 recovery is priced per member drive (based on each drive's failure type) plus a flat array reconstruction fee of $400-$800. If we recover no data, you owe nothing.
Per-Member Imaging
- Logical or firmware-level issues: $250 to $900 per drive. Covers filesystem corruption, firmware module damage requiring PC-3000 terminal access, and SMART threshold failures preventing normal reads.
- Mechanical failures (head swap, motor seizure): $1,200 to $1,500 per drive with a 50% deposit. Donor parts are consumed during the transplant. Head swaps and platter work are performed on a validated laminar-flow bench before write-blocked imaging.
Array Reconstruction
- $400-$800 depending on member count, filesystem type (NTFS, EXT4, XFS, ZFS, VMFS), and whether mirror pair assignments and stripe parameters must be detected from raw data versus captured from surviving controller metadata.
- For large RAID 10 arrays (12, 16, 24 members), the per-drive imaging cost scales with member count, but the reconstruction fee stays in the $400-$800 range. The reconstruction process operates on already-imaged data regardless of how many members contributed to it.
No Data = No Charge: If we recover nothing from your array, you owe $0. Free evaluation, no obligation.
Example: A 4-drive RAID 10 where two members need firmware repair and two are healthy reads: 2 drives at the firmware tier + 2 drives at the logical tier + $400-$800 reconstruction.
RAID 10 vs RAID 01: Why Construction Order Matters for Recovery
RAID 10 (stripe of mirrors) and RAID 01 (mirror of stripes) use identical drive counts and deliver similar performance, but their failure behavior and recovery characteristics are different.
RAID 10 (Stripe of Mirrors)
- Data is mirrored within pairs, then pairs are striped.
- Single failure degrades only one mirror pair. The rest of the array remains fully redundant.
- Survives multiple failures as long as each mirror pair retains one member.
- Recovery from a failed pair requires restoring just one of the two member drives in that pair.
RAID 01 (Mirror of Stripes)
- Data is striped across sets, then those sets are mirrored.
- Single failure degrades an entire stripe set. The surviving mirror holds all data, but any second failure in that mirror causes total loss.
- Cannot tolerate two failures in different stripe sets, even if they affect different physical drives.
- Recovery requires at least one complete, intact stripe set.
Most enterprise controllers default to RAID 10 for this reason. RAID 01 configurations are uncommon but do appear on older HP and IBM hardware. During recovery, correctly identifying whether the array is 10 or 01 is essential because the mirror pair assignments and stripe boundaries differ between the two layouts.
Enterprise RAID Controllers We Recover From
Hardware RAID controllers store configuration metadata in proprietary formats on the member drives and in onboard NVRAM. Recovery requires parsing this metadata to map mirror pairs and stripe order.
Dell PERC
H730, H740, H755 controllers used in PowerEdge servers. PERC stores DDF (Disk Data Format) metadata and controller-specific configuration data on each member. When a PERC controller fails, importing to a replacement unit sometimes alters member ordering. We read metadata from the raw drive images directly.
HP Smart Array
P408i, P816i controllers in ProLiant servers. HP uses a proprietary metadata format stored in reserved sectors at the end of each member. Cache module battery failures can cause write-back cache data loss on top of the array failure itself.
LSI MegaRAID
9361, 9460, 9560 series controllers found in a wide range of server and workstation platforms. LSI metadata is stored on each member and references virtual drive groups and span definitions. PC-3000 RAID Edition includes parsers for LSI metadata formats.
Software RAID configurations (Linux mdadm, Windows Storage Spaces, ZFS) store their metadata in standardized superblock locations. These are easier to parse than hardware controller formats but still require correct identification of mirror pair groupings and stripe chunk sizes during reconstruction.
RAID 10 Recovery Questions
How many drives can fail in a RAID 10 before data is lost?
What is the difference between RAID 10 and RAID 01?
Can a RAID 10 be recovered if a full mirror pair fails?
My RAID controller died. Can you rebuild the array without the original hardware?
How long does RAID 10 recovery take?
Need your RAID 10 array recovered?
Free evaluation. No data = no charge. Mail-in from anywhere in the U.S.