It happens quite often, the IP cameras are showing up fine on the screen and suddenly you see the “Cannot find network host” on the screen. The No Network Host error message is an indication that the IP address of the cameras you have added to your NVR have changed.
Usually, this error message can occur with cameras connected over a Power over Ethernet (PoE) switch. If you are connecting your cameras to a PoE switch and you have a power outage or network issue this may result in your camera(s) IP address changing. Fix this error message by configuring the IP address of your camera to a static IP.
How to fix the “cannot find network host” issue
This issue commonly happens if you have some cameras on a PoE switch or connected somewhere other than your NVR. If the cameras on the switch were not given a static IP address when they were initially added to the system then they will periodically get assigned a new IP address. When the camera gets a new IP address you will lose it from the NVR and you will see the Cannot Find Network Host error.
Step 1. Remove the camera’s IP address (that doesn’t work) from the Device List on your NVR. Go to the Main Menu > Camera > Remote Device and click X on the camera that shows the no network host error.
Step 2. Set the camera on the static IP. Run the Configtool and find out what’s the IP of the camera (or you can find it via the NVR > Remote Device and click Device Search). Once you know the IP of the camera, access it through the web browser.
Once you have logged into your web UI, navigate to the TCP/IP menu of your device by going to, Setup >Network > TCP/IP. In this menu you will notice a field labeled Mode. In the mode field, click on the Static radio button to change the IP address of your device from DHCP to static. Set a unique IP address that matches your network and the NVR’s IP address, use the right Gateway and Subnet Mask. Once this is complete, press Save to save your settings.
Step 3. Go back to the NVR’s Remote Device section, search for the Devices and add the IP camera to the Device List. Wait 2 minutes and the status icon will become green.
After this you’re done, next time the PoE switch goes offline or camera reboots, the IP address of the IP camera will remain the same and the NVR will be able to access it.
The ”No network host” error on a PoE NVR
This error can also be received if you have swapped camera ports with another camera at the back of the NVR with built-in PoE switch. Meaning that you unplugged a camera from port 1 for example then unplugged the camera from port 2 and then plugged the camera from port 2 into port 1 and the camera from port 1 into port 2.
The NVR will remember what camera was plugged into what port. So when you swap camera ports this can create an error in the configuration file. The NVR sees the two cameras and sees that they are in the wrong ports. It will then attempt to correct the issue which will result in the cannot find network host error.
To fix this you will need to perform a factory reset of the system to clear the bad configuration file. Unplug all of the cameras from the back and perform a factory reset on your Dahua NVR (via the Settings > Factory Default). Then plug each camera in one at a time. Wait until the camera appears on the screen before plugging in another camera. Do this until all of the cameras have been plugged in.
Bad cables can cause “Cannot find network host” issue
The last possible reason is a bad connection. This could be a bad cable or poor connection at the NVR or camera. Check that both ends of the cable are securely plugged in. If you have another cable that you know for a fact is good and working then try using that cable on that camera. If the camera works with the new cable then you need to replace the old cable.
If the camera still does not appear then check that it is getting power by covering the camera for a minute or so. The Infrared LEDs should come on. This indicates that the camera is getting power. If the lights do not come on then it is possible that there is a problem with the PoE on that particular port or there is a problem with the camera.
Try plugging the camera into an empty port and see if it comes on. If it does then it is likely that the other port is bad. If it still does not come on then there is an issue with the camera.
Note: this guide works for Dahua and their OEMs sold under these brands: Activecam, Advidia, Amcrest, Ameta, Ascendent, Backstreet Surveillance, BV Security, CCTV Security Pros, CCTV Star, CP Plus (Orange Line), Dax Networks, eLine, ENS (formerly Eastern CCTV and SavvyTech), Expose, Lorex, GSS, Honeywell, IC Realtime, Ikegami, Impath Networks, Inaxsys, IndigoVision, Infinity CCTV, Innekt, Intelbras, KBVision, Lumixen, Maxron, Montavue, Oco, Optiview, Rhodium, RVI, Saxco, Security Camera King (Elite), Space Technology, Speco, ToughDog, Tyco Holis, Tyco Illustra Essentials, Unisight, VIP Vision, Watchnet, Winic, Zuum.