nvr stops recording when network cable unplugged, how to fix?

wozzzzza

Pulling my weight
Jan 5, 2015
438
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NVR4104HS-P-4KS2 4CH , whenever i pull the network plug to the network so its a self standing unit the damn things stops recording.
how do i fix this??
 
anyone??? the screen just displays "the login return time is up" where camera image is supposed to be.
 
Provided a network diagram with IP addresses . Include at least the router, PCs,Cameras
 
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NVR4104HS-P-4KS2 4CH , whenever i pull the network plug to the network so its a self standing unit the damn things stops recording.
how do i fix this??

Hi @wozzzzza

Seems very strange....

Are the cameras plugged into the PoE ports and using the IP addresses of the NVR's PoE ports? ( checking that the camera's ip addresses are correctly setup )
 
Just to confirm - the camera is connected to an NVR PoE port, not out on the LAN?
yes camera plugged into the back of the NVR where there is 4 POE ports.
Sounds like a Non NVR POE Port.
they are all labelled POE
Hi @wozzzzza

Seems very strange....

Are the cameras plugged into the PoE ports and using the IP addresses of the NVR's PoE ports? ( checking that the camera's ip addresses are correctly setup )
IP of NVR is 192.168.1.98
IP of camera is 192.168.1.99
 
The NVR has two IP addresses. What are they ? They should be on two different subnets. If they are on the same subnet that could be the cause of tour problem.

Most of the time the NVR POE switch does not use 192.168.1.xxxx it uses something like 172.xxx.xxx.xxx
 
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IP of NVR is 192.168.1.98
IP of camera is 192.168.1.99
^^ THIS ^^ ... doesn't seem like your cameras were added under the subnet of the NVR, but rather under the router's subnet. Therefore the cameras network route is dependent on the connection to the router, hence when you disconnect the network cable the camera has no route to the NVR.

Even though the camera is physically linked to the NVR it doesn't mean it will route the traffic directly to the NVR if your network isn't setup correctly.

Basically your camera(s) and NVR are likely under the subnet of the router, but to do what you want (have a free-standing network contained within the NVR and the camera(s)) you'll need to setup the NVR to be a switch and for the camera's to have their default gateway point to the NVR's IP as their default gateway.

So right now the network path from the cameras to the NVR is probably like so, where the camera is looking for the route to the NVR, it must ask the router:
[IP_CAM (192.168.1.99)] -> [NVR (192.168.1.98), asks "Where's the default gateway of 192.168.1.1?" answer: at the router] -> [Router (192.168.1.1), asks "Where is 192.168.1.98 ?" answer: "at the NVR"] -> [NVR (192.168.1.98)]

This is because the default gateway on the cameras is probably 192.168.1.1 (the router's IP).

Typically you'll want to setup the NVR as it's own subnet (usually 10.1.1.1/24), hence the camera should have a 10.1.1.X ip address, so the network path to/from the NVR is direct, for example:
[IP_CAM (10.1.1.99)] -> [NVR (10.1.1.1), asks "Where's the default gateway of 10.1.1.1?" answer: right here]
 
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The NVR has two IP addresses. What are they ? They should be on two different subnets. If they are on the same subnet that could be the cause of tour problem.

Most of the time the NVR POE switch does not use 192.168.1.xxxx it uses something like 172.xxx.xxx.xxx
ok of course. so you referring to these? so what do i make the switch part then? or what do i make the camera?

1583708634841.png

1583708808004.png
 
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@wozzzzza Those network setting look correct, the NVR's network switch is the 10.1.1.1/24 subnet. Now you'll need to go to the camera management page and either modify their Default Gateway to be 10.1.1.1, or better yet just delete the cameras and re-add them and make sure they are added with the 10.1.1.1 Default Gateway, and that they get a 10.1.1.X IP address.
 
@wozzzzza Those network setting look correct, the NVR's network switch is the 10.1.1.1/24 subnet. Now you'll need to go to the camera management page and either modify their Default Gateway to be 10.1.1.1, or better yet just delete the cameras and re-add them and make sure they are added with the 10.1.1.1 Default Gateway, and that they get a 10.1.1.X IP address.
perfect, forgot all about that, been couple years since i set up my last CCTV network.
working all good now.
 
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^^ THIS ^^ ... doesn't seem like your cameras were added under the subnet of the NVR, but rather under the router's subnet. Therefore the cameras network route is dependent on the connection to the router, hence when you disconnect the network cable the camera has no route to the NVR.

Even though the camera is physically linked to the NVR it doesn't mean it will route the traffic directly to the NVR if your network isn't setup correctly.

Basically your camera(s) and NVR are likely under the subnet of the router, but to do what you want (have a free-standing network contained within the NVR and the camera(s)) you'll need to setup the NVR to be a switch and for the camera's to have their default gateway point to the NVR's IP as their default gateway.

So right now the network path from the cameras to the NVR is probably like so, where the camera is looking for the route to the NVR, it must ask the router:
[IP_CAM (192.168.1.99)] -> [NVR (192.168.1.98), asks "Where's the default gateway of 192.168.1.1?" answer: at the router] -> [Router (192.168.1.1), asks "Where is 192.168.1.98 ?" answer: "at the NVR"] -> [NVR (192.168.1.98)]

This is because the default gateway on the cameras is probably 192.168.1.1 (the router's IP).

Typically you'll want to setup the NVR as it's own subnet (usually 10.1.1.1/24), hence the camera should have a 10.1.1.X ip address, so the network path to/from the NVR is direct, for example:
[IP_CAM (10.1.1.99)] -> [NVR (10.1.1.1), asks "Where's the default gateway of 10.1.1.1?" answer: right here]
Dahua's NVR's historically have never let you put your management network settings on the same subnet as the(Internal) switch's(cameras) settings, I do not see how those cams on the same subnet as the management port could even see the router let alone talk to it. There is no (Direct) pass through from the the management side to the switch side and vise versa. Basically there is no bridge mode on those NVR's.
 
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