Zoneminder is a pretty solid setup for IP security cameras, and the zmninja app is really nice too. I had tried it years ago but got back to it recently with some sketchy IP cameras. I just put them in their own VLAN, no Internet access, Zoneminder does motion detection and event recording, and so far I’m quite pleased with it.
Zoneminder is best for a low-power system. In the last year or so, it got proper passthrough support so it can record video straight off the camera with zero processing. You don’t get alarms or motion detection or live view, but you can record 24x7 using 2% of your CPU.
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If you get a camera with built in detection like a Reolink I think you can trigger off the camera alarm. It is not easy though, takes some scripting. It is not great but better than nothing.
I set up a low res feed on Modect and use that to trigger recording the event on the second high res camera channel on Nodect, that keeps the CPU usage reasonable.