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Four Disks Out of a Retired NAS, Ten Years On

A software firm in Reading retired a four-bay NAS during an office move and put the disks in a box, on the reasonable assumption that they could always be plugged in again. A decade later a customer asked for something only that archive held. The disks went back into a spare enclosure and it refused to bring the volume up. There was no configuration file, no note of the order, and nobody left who had set it up.

RAID / NASRAID FailureNot Detected
// the job in four lines
MediaFour disks lifted out of a four-bay NAS a decade ago and stored loose since. Returned to an enclosure, they do not present a volume, and no record of the original configuration survives.
What was reportedFour NAS disks removed around the time of an office move, kept in storage since, will not bring a volume up when reconnected, no configuration record, no member order known, an archive needed for a customer request.
Fault classLogical, at the array level. The disks themselves were readable. What had gone was the arrangement: member order, block size and parity layout, all of which live in metadata that the enclosure could not agree with. Nothing needed rebuilding on the disks; the set needed reassembling in software.
On the benchEach disk attached separately behind a hardware write blocker on PC-3000 UDMA and profiled, all four imaged on DeepSpar with no member ever asked to rebuild, the array metadata read out of the images, member order and geometry confirmed by testing candidate layouts against filesystem structures rather than by trusting labels, the volume assembled virtually in UFS Explorer and R-Studio, files validated and written to fresh media.
// reading the fault

Reading the fault

An array is an arrangement, and the arrangement is the fragile part. Four disks holding fragments of the same files are useless until you know which disk came first, how large each block was and where the parity sat. That information normally lives in metadata the enclosure writes, and enclosures a decade apart in firmware do not always read each other's.

Putting them into a spare enclosure was the risk, not the storage. A NAS that does not recognise a set will often offer to initialise it or start a rebuild, and either of those writes to the disks. They were lucky: the box declined to do anything, and they stopped there instead of clicking through.

Ten years in a box does nothing to a disk. Magnetic storage does not fade on a shelf on any timescale a business cares about. All four spun up, all four readied, and all four read at full speed. The archive had been intact the whole time; it was simply unreadable in the form it was in.

Reassembly is done on copies, and it is done by testing. Once each member is imaged, candidate layouts can be tried against the images as often as needed. The right one is the one where directory structures and file signatures line up across the stripe, which is a matter of proof rather than of guessing, and no attempt can damage anything because the originals are not involved.

// bench work

Bench work

Each disk was attached on its own, behind a hardware write blocker, and profiled before anything else. All four were healthy, with modest defect lists and nothing mechanical to report. They were imaged one at a time on DeepSpar, and at no point was any of them put back into an enclosure or allowed to start a rebuild.

The array metadata was then read out of the images. It gave a partial picture, so the remainder was established by testing candidate member orders and block sizes against the filesystem: the correct layout is the one where directory entries resolve and file signatures survive across stripe boundaries. With that fixed, the volume was assembled virtually in UFS Explorer with R-Studio used as a second reading, and the archive was validated before being written to fresh media.

// what went back

What went back

The whole archive came back, including the project the customer had asked about and a decade of correspondence nobody had expected to see again. It went back as an ordinary folder tree on a single drive, so that the next person to need it does not need an enclosure to read it.

Multi-disk sets are quoted from £500 + VAT, which is what this was: four members, imaged individually, reassembled in software. The work was logical from start to finish, with no opening and no donor parts, so the guarantee applied in full and no fix, no fee held.

Disks out of an old NAS or server

Do not put them into a different enclosure to see what happens. A box that does not recognise a set will frequently offer to initialise it, and some models start a rebuild without asking clearly, which overwrites the parity you need. If a rebuild has already begun, pull the power rather than let it finish. Label the bay order if you still can, though it is recoverable without labels. Send every member, including any disk you believe has failed, because parity is calculated across the whole set and a set is easier to reassemble complete. Nothing here is booted, and nothing is written to a member disk at any stage.

Reading this and recognising your own drive? Every job on this page started the same way. Examining the media costs nothing, the examination closes 2 working days after the parcel is booked in and not sooner, and what comes out of it is a single figure in writing that then stays where it was put. A finished single-drive recovery leaves here 2 to 4 working days after that. Payment follows one published sentence: no fix, no fee all jobs except electronic and mechanical failures, chip level work, DVR and Forensic jobs. Deletions, damaged file systems, lost partitions, firmware and service-area repair therefore all carry the guarantee. Physical work does not: a drive opened under laminar flow, a repair to a board or to a memory chip, liquid or fire damage. Those take 50% of the quoted figure before anything starts, and the remainder falls due only if your files come back. The figures themselves are short: a memory card, a USB stick or a pen drive is £250 + VAT, any one hard drive or SSD including NVMe is £300 + VAT, and arrays, NAS boxes and servers are quoted from £500 + VAT. Recorder disks, BitLocker volumes and forensic work are quoted apart from those and settled in advance. Where the storage is bolted inside a laptop, a tower, a Mac or a server, free it and post the bare unit: taking machines apart is not work this lab does, and flash soldered flat onto a mainboard, which is how Apple Silicon Macs and a good many thin ultrabooks are built, cannot be taken in at all. Nor can phones or tablets. If it unscrews or unplugs, it is our sort of job. Send it tracked and insured to Guildford Data Recovery, Building 2, Ground Floor, Guildford Business Park, Guildford GU2 8XH, or book a courier yourself; the Guildford reception also takes devices in person, Mon–Fri 9:00am–5:30pm. Nobody collects, and there is no counter in Bracknell to call at. Freephone 0800 689 0668. Packing notes and the shipping form live here.
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These files are written up from genuine enquiries taken from households and businesses in Bracknell, across Berkshire and Surrey and into London, with names, firms and anything else identifying stripped out. Each one sets down how the fault was reasoned through, the method it actually needed and the equipment it was worked on. One of them is a job that was turned away, which belongs here as much as the rest of them.

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