Camera discovery and DHCP service
In order for the FortiRecorder NVR to be able to discover cameras and receive video, cameras must first get their IP addresses and other network settings from either the FortiRecorder built-in DHCP server or any other third-party DHCP server on your network.
• FortiRecorder DHCP server — If you do not have a DHCP server in your network, or you are installing the FortiRecorder and the cameras in their dedicated network, you must configure the built-in DHCP server on the FortiRecorder. For example, if you configured the built-in DHCP server to provide DHCP service through port2, and port2 is connected to a PoE switch, you would connect the cameras to the PoE switch. The switch would supply power to the cameras, and through it, the cameras would be able to access the DHCP server. For information about FortiRecorder DHCP server configuration, see
“Configuring the DHCP server” on page 23.
• Other DHCP server — If you already have a DHCP server in your network and the FortiRecorder and cameras will be installed in the existing network, the cameras will get their IP addresses from the DHCP server after you connect and power up the cameras.
| If you connect a camera to FortiRecorder before any DHCP server is configured, the camera will assign itself a default IP address, which might not be working in your subnet. In this case, you must reboot the camera after you have configured a DHCP server, so that the camera can get network settings from the DHCP server. |
Since you can configure the camera to use a static IP address, you only need the DHCP server for the initial camera discovery.
Later, after each camera has network settings from DHCP, you can either:
• Continue using DHCP— Leave the cameras plugged into their current network location. Configure the DHCP server to reserve a specific IP lease for each camera. This will mimic configuring the cameras with a static IP address, yet will provide the advantage that IP addresses remain centrally managed.
| If you continue to let your cameras use DHCP, you should configure Reserved IP Address (or, on a third-party DHCP server, the equivalent setting). Failure to do this may appear to work initially, but eventually could periodically, temporarily interrupt connectivity with the NVR, resulting in lost video. This can happen if either the DHCP pool is too small for the number of cameras, or if a misconfigured computer accidentally takes a camera’s DHCP lease: the DHCP server will ultimately be forced to assign the camera’s IP address to a different client. If this happens, when the camera next requests a lease, it will receive a new, different IP address, and the NVR will not be notified. Connectivity interruptions are usually self-correcting: within a few minutes, the FortiRecorder NVR should detect the camera’s IP address change. To restore connectivity manually, either manually update the camera’s definition on the NVR to reflect the new IP, or discover the camera again. |
• Switch the camera to a static IP — Use the FortiRecorder NVR to configure the camera with a static IP address. This removes the requirement of your cameras to remain within reach of the DHCP server, which provides 2 advantages:
• You can disable DHCP if not otherwise required (recommended for better security).
• You can move the cameras to a remote location on your network that would not ordinarily be reachable by your DHCP server.