The cameras show live video, but when you go back to find footage from an hour ago, nothing's there. This is almost always one of: storage full, schedule not set, hard drive failing, or wrong recording mode.

1. Check storage status

Most NVRs have a system status page showing:

  • Free space — should be > 0 and showing normal usage
  • Hard drive health — should say "Normal" or "Good"
  • Recording status per camera — green or "Recording" next to each

If storage shows 0 free and the NVR is set to overwrite oldest, that's normal — it should be recording. If the NVR is set to "stop when full", it stops recording until you free space.

2. Hard drive health

NVRs typically have 1-4 hard drives. If one shows:

  • Warning — drive is failing; replace soon
  • Error — drive has failed; data on it is lost
  • Not detected — drive is unplugged or completely dead

Drives in 24/7 NVRs live around 3-5 years before warning signs appear. Replace at the first warning, not after failure.

3. Recording schedule

Each camera has a recording schedule. If the schedule was cleared or modified:

  • Look at the schedule grid for each camera
  • Confirm it covers the times you expected recording
  • Default is usually 24/7 continuous + motion detection

Common mistake: switching from continuous to motion-only and then wondering why long quiet periods have no recording.

4. Recording mode (continuous vs. event)

NVRs offer:

  • Continuous — records 24/7
  • Motion-triggered — records only when something moves
  • Event-triggered — records on alarms, line crossing, etc.
  • Scheduled — only during set hours

If you wanted continuous and it's set to motion, switch back.

5. Disk fully formatted but new

If the disk is new and showing as detected but no recording:

  • Format the disk through the NVR menu (NOT from a PC — the NVR uses its own filesystem)
  • After format, recording should start

6. The "stop on full" trap

By default, modern NVRs overwrite oldest footage when storage fills. If the NVR is set to "stop on full", and you didn't notice, recording stopped weeks ago when storage filled.

Change to overwrite mode in settings.

7. Network bottleneck

For network-based recording (cameras streaming to NVR), if the network is congested:

  • Some frames are dropped
  • Recording may look choppy or have gaps

Check the camera bitrate settings. 4K cameras at high bitrate (8+ Mbps each) saturate a 100 Mbps switch quickly.

8. Power interruption

If the NVR lost power suddenly:

  • The current recording file may be corrupted (a few minutes lost)
  • The disk may need a filesystem check (run from NVR menu)
  • UPS-backed NVRs avoid this; if yours isn't on UPS, consider adding one

9. Specific camera not recording while others are

If most cameras record fine but one doesn't:

  • Check that specific camera's schedule
  • Check the camera's connection (PoE LED, ping the camera IP)
  • Verify the channel assignment hasn't been changed accidentally

10. Recovering recently lost recordings

If recordings were just deleted:

  • Stop using the NVR immediately (further writes overwrite the deleted blocks)
  • Some NVR vendors have data recovery tools; ask the vendor
  • For evidentiary recovery, hire a forensic recovery firm

When to ticket

Raise a ticket if:

  • A drive shows Warning or Error status
  • Recordings are missing despite correct schedule and adequate storage
  • You need a drive replacement
  • You suspect the NVR clock has been wrong (recordings exist but timestamps are off)

Include the NVR model, what camera(s) are affected, the date range you expected to find footage from, and what storage shows.