Do not rebuild, re-initialise or reformat the array. Shut the server or enclosure down, label every disk with its slot number and keep the disks in their original order. A forced rebuild on a damaged array can overwrite the data you are trying to save.
What each RAID level can survive
- RAID 0 stripes data across disks with no redundancy, so one failed disk takes the whole array down
- RAID 1 mirrors two disks, so either one can fail
- RAID 5 survives one failed disk and RAID 6 survives two
- RAID 10 stripes across mirrored pairs and survives one failure in each pair
Go past those limits and the volume disappears. It happens more often than people expect, because disks bought together tend to wear out together, and a rebuild is the hardest work the surviving disks will ever do. We recover standard and nested RAID levels.
RAID levels we recover 17 listed
- RAID 0
- RAID 1
- RAID 3
- RAID 4
- RAID 5
- RAID 6
- RAID 1E
- RAID 5E
- RAID 5EE
- RAID 10
- RAID 50
- RAID 51
- RAID 01 (RAID 0+1)
- RAID 03 (RAID 0+3)
- RAID 10 (RAID 1+0)
- RAID 50 (RAID 5+0)
- RAID 60 (RAID 6+0)
Disk faults and array faults
Physical faults are in the disks themselves: failed heads, bad sectors, a clicking drive, a seized motor, a burnt-out PCB, corrupt firmware or damaged platters. Each failed disk is a recovery in its own right, done in an ISO Class 5 (Class 100) clean room, before the array can be put back together.
Logical faults leave the disks healthy but the array unreadable. A dead RAID controller, a rebuild that stopped halfway, an accidental reformat, deleted files and partitions that no longer mount all fall here. The job is to work out the original disk order, stripe size and parity layout, then reassemble the volume.
RAID recovery prices
| Array | Guide price |
|---|---|
| Initial consultation | Free |
| RAID 0 | £650 + VAT |
| RAID 5, 6 and 10 | £850 + VAT to £1,500 + VAT, depending on the number of drives |
Other levels are quoted after the free consultation. The quote is firm, and if we cannot recover the data you do not pay. See the full data recovery price list.
Getting an array to us
Bring the disks or the whole unit to 68A North End Road, or we will collect it free of charge. For a server that cannot easily leave the building, a technician can come to your office. A senior technician is on standby 24/7 for urgent data loss, and everything on the array is treated as confidential.
If your array lives inside a Synology, QNAP or similar box, start with the NAS data recovery page. Single drives are covered under hard drive data recovery, and the main data recovery page explains the whole process.
Questions people ask
One disk has failed and the array is still running. What should I do?
Copy your most important files to another device while the array is still up. Then speak to us before you replace the disk and start a rebuild, because a second failure during a rebuild is a common way to lose an array.
The RAID controller has died. Is the data lost?
Not usually. The controller manages the array, but the data lives on the disks. Do not connect them to a different controller and accept an offer to initialise them. Keep the disks in order and bring them to us.
How much does RAID recovery cost?
As a guide, RAID 0 is £650 + VAT. RAID 5, 6 and 10 run from £850 + VAT to £1,500 + VAT depending on the number of drives. The consultation is free and you get a firm quote before we begin.
Can you work on site?
Yes. A technician can visit your workplace, and some problems can be diagnosed remotely over the internet. Disks with physical damage have to come to the clean room.