There's no need for a RAID 5 to be lost when one of its disks drops out, or when the rebuild fails mid-rebuild or if the controller dies; the member drives will usually still contain all the data you require. All drives will be imaged to allow us to re-assemble the RAID in software without ever writing to an original drive.
Every RAID case starts with a free diagnostic. Pricing is from £500 + VAT, priced per disk, and prior to starting recovery work we will provide you with a single written quote. On logical rebuilds, in most cases you only pay if we recover your data.
The first disk failure can leave you still able to recover in RAID 5. It's the second failure that causes the problem. These are the types of failure we see from Swansea servers and NAS systems.
Swapping for a replacement drives many hours of heavy reads on existing old and weary survivor disks. If one of them gives up while being used during the rebuild process, a degraded array becomes a dead one, which is far and away the most common type of RAID 5 emergency.
This problem can come from a dead HBA (host bus adapter), controller or backplane. Your disks can be perfectly healthy, but as long as there is some type of failed hardware surrounding them the volume can't be accessed until both the configuration and parity metadata are retrieved from each member, even though the data itself is intact.
If a disk drops from the array and then gets put back in later, the data on that disk will have been frozen at the point in the past when it was last active. The other disks however are able to continue working as usual. When the old disk is added back into the array (re-added), the data that had been written since this disk left the array is going to be intermixed with what existed prior to the disk leaving. As a result of adding an older disk to the array, parity values across every stripe will become corrupted.
When you encounter a read error on one disk, parity can handle this, but if there are matching errors in the same place on two disks, parity cannot fix this. Therefore we image around the weak sectors on every member disk before attempting any reconstruction.
Using the 'repair' options on the dashboard, recreating the array or reinitialising it can overwrite the metadata describing where your actual data resides.
Expanding to add space or changing from one RAID level to another takes a long time and is fragile. If interrupted part-way through this process, the array will be left stranded between two layouts and nothing on it will mount.
None of our recovery steps touch your original disks. First, each member is imaged to a stable image using hardware imaging systems; before that, if there was mechanical failure in one of the drives it would have been repaired on the bench. After that we work out from the images which order the disks go in, what the stripe size is, how they rotate, and which direction the parity runs. Then we create an assembly of the virtual array and pull your files off, and the originals remain untouched throughout as the final fallback.
Dropping in a new disk to let the controller "rebuild" appears to be doing something useful, however, on an array that has already used up its safety margin it will put you at your greatest risk; the remaining healthy disks will be running at maximum capacity just when they are at their weakest point, and if another disk fails while rebuilding then what was once recoverable becomes a hard case. If a rebuild has already stalled or thrown errors, shut the machine down and leave it that way.
The majority of RAID 5 systems we receive here are used as primary data stores for small businesses, mainly Dell PowerEdge, HP ProLiant and Lenovo servers, bespoke builds and Synology, QNAP and Netgear NAS systems from businesses throughout Swansea, Llanelli, Neath, Port Talbot and the M4 corridor. Following quotation, the disk drives are then posted into our Bristol location, tracked and insured, with each drive labelled according to its position (bay). Alternatively the disk drives can be dropped off there Monday to Friday, 9am to 5:30pm, with no appointment needed. Business-critical arrays can be moved to the front of the bench. For details see our RAID recovery service and NAS recovery service pages, and see our data recovery costs page for information regarding prices.
Just shut it down (if it's running), obtain a quote for the rebuild, send us the member disks and we'll rebuild it all virtually, with a complimentary diagnostic and a fixed written quotation to price out the rebuild before we begin.
First get a quote over the telephone or use our free on-line diagnostic. The majority of customers then have their media sent to us via post, this is tracked and insured.
Do you want to send a drive from your computer, laptop, MacBook, iMac, CCTV / DVR or server? Please do not send the complete unit of computer or device with a hard disk drive (HDD) or solid state drive (SSD) inside. Please remove it and only send the drive itself. For a server, please remove all disks and label them by their bay. We will also not perform removal of internal drives from devices in order to access data. Also, we will not extract data from devices where storage is soldered onto the motherboard (such as T2 and Apple Silicon Macs and some thin laptops). Additionally, we do not recover data from phones and tablets, only drives that can be removed and sent to us. If you're not sure which kind you have, ring us first.
↓ Print the booking-in & shipping form (PDF)
Clearly mark the parcel with the name Bristol Data Recovery, and when your media has been diagnosed we will call you immediately.
If unsure about what to post, please call us first on 0800 689 0668 (the free phone number), or complete a free online diagnostic.