A law firm’s QNAP NAS in RAID 1 stopped mounting after a power failure — confidential case files locked away, the array showing as degraded. Both disks were fine; a corrupt partition table was blocking access. RAID 1 keeps a full copy on each disk, which makes it the most recoverable layout there is — but also means corruption hits both mirrors at once. We imaged the disks, repaired the partition, and recovered every document.
A law firm ran its document store on a QNAP NAS configured as RAID 1 — two disks holding mirrored copies of confidential client files, contracts and case records. After a power failure the NAS would no longer mount the volume: the QNAP interface reported the RAID 1 array as degraded or unavailable, the disks appeared functional but wouldn’t mount on any computer, and disk tools showed the partition structure as missing or unreadable. With privileged legal material at stake, confidentiality and a careful recovery mattered as much as speed, so the firm stopped using the NAS and sent the disks to us under an NDA rather than risk making things worse.
RAID 1 is the simplest form of redundancy: two disks holding identical, mirrored copies of the same data, written in lockstep. Its purpose is to keep you running if a disk dies — lose one, and the other still holds a complete copy. That mirroring is also why RAID 1 is, of all the RAID levels, the most straightforward to recover from. Unlike RAID 0, 5 or 10, there is no stripe geometry to reconstruct: data isn’t split across disks, so each disk is a full, self-contained copy of the volume that can be read on its own. When the disks themselves are healthy, as they were here, recovery is usually a question of fixing the file system on top — not of rebuilding an array.
The fault was a corrupt partition table, caused by the power failure interrupting the NAS mid-write. The partition table is the structure that tells the system where the volume starts, how big it is and how it’s formatted; damage it and nothing — not the QNAP, not a computer — can find the file system, even though the files are all still present. Here is the catch that surprises people, though: because RAID 1 mirrors everything in real time, it faithfully copied the corruption to both disks at the same instant. RAID 1 protects you against a disk dying, but it offers no protection against corruption, accidental deletion or ransomware — whatever happens to one disk happens identically to its mirror. Redundancy is not a backup, and this is exactly why.
Before any technical work, the job was set up to keep the material confidential: it was handled under a non-disclosure agreement, worked on in isolation, and the recovered data would be returned on an encrypted drive. For legal, medical and other sensitive recoveries that chain of confidentiality is part of the job, not an afterthought — and being ICO-registered and GDPR-compliant, it’s how every such case is treated.
Both disks were cloned sector by sector to healthy storage through write blockers, so all work happened on copies and the originals were never altered — important for both safety and confidentiality. A health check confirmed both drives were physically sound, matching the diagnosis of a purely logical failure. Working from an image, the damaged partition table was manually reconstructed — re-establishing where the volume began and how it was formatted — and the underlying Linux file system was repaired so its structures were consistent again. Because RAID 1 gave two identical copies, we could also cross-check between the mirrors to confirm the reconstruction was correct. With the partition and file system restored, the volume mounted and its contents became readable.
The firm’s data was extracted in its original structure — case files, client records, contracts, emails and legal research — and every document checked to confirm it was intact and uncorrupted before sign-off, which matters especially where files may be relied on professionally. The complete set, a full recovery, was returned on an encrypted external drive. The advice we left the firm with is the crucial one for anyone trusting a NAS: RAID 1 (or any RAID) keeps you running through a disk failure, but it is not a backup — a power cut, corruption or a mistaken deletion is mirrored instantly to both disks — so a separate, ideally offsite, backup is what truly protects irreplaceable records.
Per-disk sector imaging through write blockers · manual partition-table reconstruction · Linux file-system repair · cross-verification between RAID 1 mirrors · confidential handling under NDA with encrypted return. All work in-house at our Belfast lab.
A RAID 1 that won’t mount is usually a logical fault, not lost data — and the disks are often perfectly healthy. Power the NAS off and send us the disks for a free, no-obligation diagnostic; sensitive data is handled under NDA. We’ll tell you what can be recovered and put a fixed price in writing before any work starts. We recover QNAP, Synology and other NAS units for businesses across the UK.
Usually yes. A RAID 1 that won’t mount is most often a logical fault such as partition or file-system corruption, not a disk failure — and because RAID 1 mirrors data, each disk holds a full copy. When the disks are healthy, repairing the partition and file system typically brings everything back. The key is to stop using the NAS so nothing overwrites the recoverable data.
That’s how RAID 1 works: it copies every change to both disks in real time, so corruption, deletion or a power-failure fault is mirrored to both instantly. It means RAID 1 protects you if a disk dies, but not against logical damage — which is why a RAID is never a substitute for a real backup kept separately.
Yes. Sensitive recoveries are handled under a non-disclosure agreement, worked on in isolation, and returned on an encrypted drive, and we’re ICO-registered and GDPR-compliant. Confidentiality is treated as part of the job for legal, medical and business data.