I'm managing a security system with four cameras connected to an NVR, and now I'm faced with the task of choosing the right hard drive size. I've read plenty of advice online saying to just go for bigger drives, but I feel that's not necessarily the best strategy. A massive drive might not get filled before the technology becomes outdated due to firmware updates. Conversely, selecting a smaller drive might lead to constantly overwriting my footage. Has anyone tested what hard drive sizes work well for setups with multiple cameras, especially when considering the differences between recording at 1080p versus 4K?
5 Answers
I'd suggest planning for about 1TB per camera. I have a set up with six cameras, both 4K and 2K, and went with two 8TB drives in a RAID 1 configuration. That gives me around eight weeks of storage before overwriting the oldest files. Plus, my NVR allows for adding more drives later if necessary!
I've been using a 2TB drive for my four 1080p cameras. It records continuously and lasts for about six weeks before overwriting the oldest data. Just make sure to pick the biggest drive you can afford!
Buy the largest hard drive within your budget. If you’re operating multiple 4K cameras, you’ll fill that drive quickly. Besides, drives don’t really go obsolete; if your NVR needs upgrading, you can just swap the drive into the new one.
For larger server setups, I've seen capacity ranging from 48TB to 460TB, particularly using RAID 5. This might be overkill for simpler setups, but it's good to know the options out there.
Calculating your storage needs is pretty straightforward: just use the formula of bitrate multiplied by the number of cameras and how long you want to keep the footage. Don't worry about firmware; it's the drive's capacity that matters.

Right! It's crucial to clarify how long you usually keep the footage. I personally only save about two weeks' worth.