NVR+HDD: the NVR is connected to the network camera, it is recommended to fix the IP address of the NVR. In the system configuration, network configuration, basic configuration interface, do not enable automatic acquisition of the IPV4 address, manually assign an IP to the NVR. In this case, in the case of an external network interruption, as long as the LAN is connected [the network between the camera and the NVR] without interruption, the recording will continue. The NVRis connected to an analog or coaxial camera, and whether the network is connected does not affect the recording. 2. IP Camera +SD card:  the external network or LAN interrupt will not affect the recording.