When a RAID 1 mirror has gone into "read-only" mode, dropped both drives or had its NAS controller fail, it still needs proper recovery, because redundancy doesn't cover corruption or a dead box. We take an image of each drive and rebuild your data safely.
Free diagnostic service with every RAID recovery project. Once an initial diagnosis has been completed, a fixed price is always quoted in writing before any work begins. Our RAID recovery prices start at £500 + VAT, based on the number of disks involved, and on logical rebuilds you only pay if we recover your data.
A mirror should survive one dead disk, although mirrors do still lose data through a shared fault, a dead controller or a bad rebuild attempt.
Since each of the two disks in a RAID 1 mirror receives the same write operations, it can tolerate the failure of one disk; however, since these disks were purchased and used as a pair, they wear at the same rate, and the same surge, temperature extremes or age can take both out together.
It is possible for the controller or bridge board in a two-bay NAS or external mirror to fail while both disks remain functional. When the controller fails, both disks must be accessed directly and the file system must be rebuilt before the mirror will mount.
If you replace the incorrect disk member or allow the device to rebuild in the wrong direction, the blank or older disk will overwrite your existing data. This would eliminate the exact files you intended to preserve.
If a mirror runs in degraded mode using only one disk, and later on the second disk alone, both of those disks now contain different versions of your data. As such, merging them incorrectly will result in corrupted files.
Due to the fact that each side of a RAID 1 mirror contains identical data, any form of logical error (corruption, deletion or a bad update) is duplicated to both sides simultaneously. Therefore, redundancy offers no protection against errors of this nature.
A failed firmware update or an operating system crash on the NAS itself could make you lose access to a perfectly healthy mirror until the volume is built back up using images.
To us, each part of a mirror is an independent hard drive. We create clones of both parts of the mirror using hardware-based imagers, and if a drive within the mirror is failing physically, we repair it on our repair bench first. We then figure out which part of the mirror holds the most complete, most recent copy of your data, restore the file system from that clone and extract your files: we never write any data onto your original drives.
RAID 1 protects against only one possible event (a single disk dying), but does not protect against deletions, formatting, corruption, ransomware attacks or failed software updates. When any of these events occurs on one disk within a mirror, it is immediately reflected on the second disk, and a controller failure can lock both disks away at once. This is why you may need "real" recovery when the mirror fails, and why you should keep a true backup on separate media.
Most of the mirrors we recover come from two-bay Synology, QNAP and Netgear NAS devices or small business servers, serving businesses and consumers in Surrey and west London. Media is posted in to our Guildford facility after a customer contacts us via phone (0800 689 0668) for a quote or uses our free online diagnostic. For other forms of arrays please visit our RAID recovery and NAS recovery pages, and see our typical data recovery costs.
We offer a free diagnostic and a fixed price quotation, and on logical rebuilds, you only pay if we recover your data. Start now, or ring our freephone number.
Before sending anything, get a quote from us either by telephone or using our free online diagnostic. Then post your hardware to us (tracked and insured), or drop it off at our Guildford laboratory in person.
Sending a drive from a computer, laptop, MacBook, iMac, CCTV/DVR or server? You will need to remove the internal hard drive or SSD and send us just the drive, as we are unable to remove the drive for you. We also cannot recover storage soldered onto a motherboard, such as in Apple Silicon Macs and some thin laptops. Only drives that can be removed from a machine and sent to us can be recovered. If you are unsure whether your device has a removable drive, please call us before sending. RAID, server and SAN drives need to be removed from their enclosure and labelled by bay. For a NAS, send the disks themselves if they are removable, otherwise the entire NAS device. An external single drive should come to us whole, along with its cable and power supply.
↓ Print the booking-in & shipping form (PDF)
Please mark the package for the attention of Guildford Data Recovery, and we will call you as soon as we have diagnosed your media.
Unsure as to how to proceed with sending the item in for recovery? Then simply call 0800 689 0668, or complete the free online diagnostic prior to dispatching the item to obtain your price quotation.