NVR storage fills predictably based on number of cameras, resolution, and how long you keep recordings. When it fills:
1. Check current storage settings
On the NVR:
- Overwrite when full — default; oldest footage automatically deleted. Recording continues.
- Stop when full — recording stops, no automatic cleanup. Easy to miss.
If yours is set to "stop when full", switch to overwrite — assuming you don't have a legal hold requirement.
2. How much do you have, and how much do you need?
Rough math:
- 1080p H.264 at 24/7 = ~10 GB per camera per day
- 4K H.265 at 24/7 = ~30 GB per camera per day
- Motion-triggered recording: maybe 25-50% of continuous
For 8 cameras at 1080p H.264 for 30 days: ~2.4 TB.
Your NVR specs show total drive capacity. If you've outgrown it, options are:
- Add more drives (if your NVR has empty bays)
- Replace drives with larger ones (if you're at max bays)
- Add a network storage device
3. Reduce retention
If you don't need 30 days, shorter retention frees space:
- Settings → Storage → set retention to X days
- Anything older is auto-deleted
Legal/insurance requirements often dictate minimum retention — check before reducing.
4. Reduce bitrate
Lower bitrate = smaller files. Tradeoff: lower image quality:
- Keep main stream at full quality for live viewing
- Reduce substream bitrate (used for recording)
- For most use cases, 2-4 Mbps at 1080p is sufficient
5. Reduce resolution
If 4K resolution isn't required, drop to 1080p — third the storage. 1080p is usually adequate for general surveillance.
6. Motion-triggered recording
Switching from continuous to motion-triggered:
- Saves storage when nothing is happening
- Risks missing slow movements the motion detector can't catch
- Requires good motion zone configuration (exclude moving trees, traffic outside windows)
For "I need to see what happened at this time" use cases, continuous is safer.
7. Adding a new drive
Most NVRs accept additional drives:
- Power off the NVR
- Open the case (check the manual)
- Connect a SATA hard drive (surveillance-rated like WD Purple or Seagate Skyhawk)
- Power on and format from the NVR menu
Don't use consumer-grade drives — they fail in 24/7 write-heavy workloads.
8. RAID for redundancy
For higher-end NVRs that support RAID:
- RAID 1 (mirror) — same data on two drives; one can fail without data loss
- RAID 5 — three or more drives; one can fail
- Cost: doubles or more your storage cost for the same effective capacity
Worth it for evidence-grade requirements (banks, secure facilities); often overkill for office surveillance.
9. Backup of important footage
For incidents that need long-term storage:
- Export the relevant footage to a USB stick or network share
- Keep on hand for the duration of investigation
- Verify before deleting from NVR
10. Cloud archive
Some vendors offer cloud archive — recent footage stays on-NVR, older moves to cloud:
- Subscription model
- Useful for organizations with limited on-site storage
- Verify your data residency requirements first (some industries require local storage)
When to ticket
Raise a ticket if:
- You need more drive bays than your NVR supports (i.e. a bigger NVR)
- A drive needs replacing (warning status)
- You need RAID set up for redundancy
- Cloud archive setup is required
Include current capacity, what's needed, and any regulatory minimum retention you have.