[Linux-based NVR's] How to configure and forward access ports in a NVR for remote viewing via iViewer or a browser

Question 

How to configure and forward access ports in a NVR for remote viewing via iViewer or a browser

Answer

Port forwarding is the process of opening specific ports on a router to allow traffic to pass through a device in your local or private network. If you have a ND NVR device and you would like to access it remotely (outside its LAN network) you will need to forward its main communication ports. 

Before starting the port forward process, you need to first verify (or set) the ports used by the NVR. Note: If you are planning on adding the NVR to the iViewer application you will also need to allow the access:

To allow access, first go to the NVR configuration, under the Network > Service > CMS & iViewer section select "Allow access" and save the configuration.

Once this has been taken care of, go to your router (or contact your ISP provider if needed) and open the following ports:

1. HTTP Port: 
   • Internal port: 80 (default)
   • External port: 80 (recommended)
2. RTSP Port 
   • Internal port: 3454 (default)
   • External port: 3454 (recommended)
3. RTSP/HTTPS Port (secure connection) 
   • Internal port: 443 (default)
   • External port: 443 (recommended)

Please note that while ports are set by default in our ND devices, you can change the configuration if needed, specially if you have multiple NVR/Devices in your network and need to set different values accordingly. As long as all the devices have unique communication ports there should not be any issues. For example, lets say that there are two NVR (NVR 1 & NVR 2). In this case you will need to assign a unique port for each device:

 
Internal IP: <NVR 1 IP>

• Internal port: 443
• External port: 443

internal IP: <NVR 2 IP>

• Internal port: 443
• External port: 444

For easier management we recommend to change the internal configuration ports of the NVR to match the external ports and avoid confusion:

Internal IP: <NVR 1 IP>

• Internal port: 443
• External port: 443

internal IP: <NVR 2 IP>

• Internal port: 444
• External port: 444

Once all the ports have been properly configured you should be able to access the NVR using a browser externally (with the router public IP and forwarded port).