Phoning home is not an Amcrest-specific thing, all of my cameras (I have a handful of Amcrest and D-Link cameras, and one Reolink camera) try to do that. I've put them all in a separate VLAN which can't access anything, not even DNS. The NVR software lives on a different VLAN and is able to open connections to the cameras for recording.
This setup works perfectly. Most importantly, the cameras all work fine even if they can't phone home.
Phoning home is not an Amcrest-specific thing, all of my cameras (I have a handful of Amcrest and D-Link cameras, and one Reolink camera) try to do that. I've put them all in a separate VLAN which can't access anything, not even DNS. The NVR software lives on a different VLAN and is able to open connections to the cameras for recording.
This setup works perfectly. Most importantly, the cameras all work fine even if they can't phone home.