Hikvision DS-7608 · DS-9632 · Dahua NVR5216 · Uniview · Surveillance Station · Milestone · SkyHawk · Purple
NVR and CCTV recorder drives drive recovery. The recorder under the counter, overwriting the week you need.
A network video recorder is a small computer with one to sixteen surveillance drives, writing a dozen camera streams at once into a proprietary block format and overwriting its oldest footage the moment it needs the space. Hikvision, Dahua and Uniview make most of them; Synology's Surveillance Station and the Windows VMS servers from Milestone, Genetec and Avigilon do the same on ordinary file systems. When a drive fails the recorder keeps running, and every hour it runs is an hour of the incident closer to gone. The recorder should be off from the moment the footage matters; the drive is imaged with the newest-footage regions last and the timeline rebuilt from the image. One recorder drive imaged is £300 + VAT after the free look, fixed in writing, 3–4 days at the bench; the eight-drive recorders are £500 + VAT upwards.
Rather talk it through? An engineer answers the bench line
0800 6890668
Models we see, family by family.
Which kind of drive is it →| Family | Model strings | Interface, capacity and notes |
|---|---|---|
| Hikvision | DS-7604, DS-7608, DS-7616, DS-9632 | 1–8 drives · proprietary block format |
| Dahua | NVR4208, NVR5216, NVR5832 | 1–8 drives · proprietary |
| Uniview | NVR302, NVR304, NVR308 | 1–8 drives |
| Synology and VMS | DVA1622, DS units; Milestone, Genetec, Avigilon servers | Ordinary file systems |
What tends to go wrong on an NVR.
NVR and CCTV recorder drives symptoms, and how long each gives you.
Not listed? Describe it on the form →What the message means on an NVR.
Describe yours to us →| What you see | The usual reason | Where that leaves you |
|---|---|---|
| Virtual or logical disk degraded | One member out; still readable | Image the weak drives before rebuilding |
| Virtual or logical disk failed | Too many members out | Every member imaged; set reassembled from images |
| Foreign configuration | Metadata the controller does not claim | Do not clear; import only with every member present |
| Predictive failure | A drive crossed its thresholds | Replace on a healthy set; image first on a degraded one |
From the parcel arriving to your files going back.
Work we have closed →Logged the day it lands, and the first look costs nothing Free
A case number goes on the parcel and a number on every drive the day it is opened, matched to the slot you wrote on it. An engineer settles what has actually happened before anything spins: the interface, the sector format, the firmware, the security state, and what the controller was saying when it stopped. Back to you come two things together: a straight note of what is liftable and what is not, plus one figure, fixed and written down. Accept it, or decline and owe us nothing.
The drive on its own bench
A member drive is read on the equipment its interface needs: a SAS imager for SAS and NL-SAS, a SATA imager for enterprise SATA, a terminated SCSI or Fibre Channel controller for the legacy drives, a PCIe adaptor for NVMe. It is never put back in a server, and never in a controller that will try to rebuild. Drives that answer at full speed are imaged; drives with weak or failed heads go to the clean bench, where matched donors are fitted and the service area repaired before a sector is read.
Imaged once, at its native sector size
Every drive is imaged sector by sector, head by head where it needs it, with the bad areas last. Drives with 520- or 528-byte sectors are imaged as they are and the extra bytes stripped from the image, never the drive. Self-encrypting drives are unlocked on the imager with the key you supply. From then on the originals are not touched again.
The image, and the set
Where the set is healthy and one member was the job, the image goes back to you on a fresh drive, sector-identical, ready to rebuild from. Where the set is the job, every member is imaged and the array reassembled in software from the images: order, chunk size, parity rotation and the reshape point read from the drives' own metadata, the file system repaired on the virtual volume, never on the originals. The array work is covered in full on our RAID array site, and it happens on the same bench.
You see the file list before you pay
What was recovered is listed for you first, and only then does a bill exist. Approve the list and it is invoiced; turn it down and it is not — and where nothing has come back, most jobs carry no charge at all. Recovered data travels home on fresh media bought in for your job, with the postage at our end. Your case is not closed until you have opened the files on a machine of your own.
From the bench
- Export the controller log first. It is the best record of what failed when, and the bench reads it.
- The drives are the job; the controller is context. Send the controller only if we ask, or if it holds a SED key.
- Keep the failed drive. It holds the stripes the rebuild could not compute, and the warranty courier takes it away.
What helps, and what harms.
Do this much first
- Export the log and photograph the screen
- Power down and label every slot
- Send the weak drives, or the set
- Tell us the controller, the RAID level and the slot numbers
What sets us back
- Rebuilding with a second drive flagged
- Clearing a foreign configuration
- Force-onlining failed drives
- Letting the engineer take the failed drive first
Questions answered before you commit.
The recorder overwrote the footage. Is it gone?
Yes. What comes back is what the loop had not reached. Power the recorder off the moment an incident matters.
Do I send one drive or the set?
One drive where the set is healthy and you want it imaged for the rebuild; every member, labelled by slot, where a second drive is flagged or the set has failed.
What does it cost?
£300 + VAT for one drive after the free look; an NVR RAID set of two to four from £500 + VAT; eight-drive recorders from £1,250 + VAT.
How long does it take?
3–4 days at the bench for one drive; 5–10 days at the bench for a set.
Begin here if yours is doing the same thing.
Nothing gets worse while it is powered down.
Looking at it is free. Back comes a list of what opened and what did not, together with a single price to finish, set down in writing while you are still free to say no. On most jobs an invoice only follows the data. Until that list reaches you, leave the server off and the drives in their slots.