Dahua NVR and camera IP addresses

[gregip]

I keep my NVR and cameras on a stand alone network. My Dahua 4216 16 PoE port NVR NIC is 192.168.2.108 with gateway 192.168.2.1. The NVR is connected to a 4G wireless modem/router.
Several Dahua cameras are connected directly into the PoE ports and the NVR automatically assigned them IPs in the 10.1.1.x range on ports 1, 2,3 etc. They all work fine.

Two other Dahua cameras are connected into a PoE switch 100m away and the switch is connected into the modem/router (via a wireless bridge just in case that matters). The camera list on the NVR's monitor shows these two cameras have unique IPs in the 192.168.2.x range on port 37777. I guess the router allocated these IPs. These work fine. One small issue is that several times a day I get a "CAM Offline Alarm" with these two cameras.

Two questions:
(1) is it acceptable for the NVR and its two switched cameras to have a different IP sub net to the other PoE connected cameras (192.168.2.x and 10.1.1.x) ?
(2) is it possible that the different sub nets are causing the CAM Offline Alarm in the two switched cameras 100m away?

 

[TonyR]

Two questions:
(1) is it acceptable for the NVR and its two switched cameras to have a different IP sub net to the other PoE connected cameras (192.168.2.x and 10.1.1.x) ?

Yes

Two questions:
(2) is it possible that the different sub nets are causing the CAM Offline Alarm in the two switched cameras 100m away?

Less likely than the fact that that the 2 cams on 192.168.2.XXX via a bridge are overtaxing the switch portion of the modem/router. What is that modem/router's switch rating?

 

[gregip]

What is that modem/router's switch rating?

The modem is a TP-Link Archer AC1200 MR600. I don't see a "switch rating" on the datasheet but the ports are labelled "Gigabit LANs" and the datasheet says "Ports: 1 10/100/1000 Mbps LAN/WAN + 3 10/100/1000 LANs".
The "CAM Offline Alarm" alert has only started since I did a firmware upgrade on the two 5442 cameras on the switch 100m away. The firmware upgrade was necessary to get the SMD feature to work.

 

[wittaj]

Cameras connected to Wifi routers (whether wifi or not) are problematic for surveillance cameras because they are always streaming and passing data. And the data demands go up with motion and then you lose signal. A lost packet and it has to resend. It can bring the whole network down if trying to send cameras through a wifi router. At the very least it can slow down your system.

Unlike Netflix and other streaming services that buffer a movie, these cameras do not buffer up part of the video, so drop outs are frequent. You would be amazed how much streaming services buffer - don't believe me, start watching something and unplug your router and watch how much longer you can watch NetFlix before it freezes - mine goes 45 seconds. Now do the same with a wifi camera and it is fairly instantaneous (within the latency of the stream itself)...

The same issue applies even with the hard-wired cameras trying to send all this non-buffer video stream through a router. Most consumer grade wifi routers are not designed to pass the constant video stream data of cameras, and since they do not buffer, you get these issues. The consumer routers are just not designed for this kind of traffic, even a GB speed router.

So even though the problem just now surfaced doesn't mean it wasn't sitting there waiting to happen. Maybe another device on the wifi is using more bandwidth, you have Alexa or some other Amazon product and now someone is sipping bandwidth through Amazon Sidewalk, a neighbor is sipping your wifi, or you have an ISP provided wifi and it is acting as a hotspot for other people on their system, or a neighbor added a wifi device and you are not getting interference. Tons of things can cripple the wifi connection, even wifi add ons you don't control like a neighbor.

My camera bandwidth demands are 350Mbps - that will bring any consumer wifi router to a standstill, even a GB router with a lot of RAM.

You need to either get a VLAN like the Edgerouter or a dual NIC system to keep those cameras from passing thru the router OR at the very least connect the cameras and NVR to the same switch and then the switch to the router.

It is weird that it happened with the firmware update, but we have seen weird things happen with updates. Did you factory reset it and then install and factory reset again? Sometimes things get stuck in an update and maybe it is causing the issue?

 

[gregip]

OR at the very least connect the cameras and NVR to the same switch and then the switch to the router.

Thanks wittaj, I think that's a great idea. I'll call the switch 100m away with two cameras switch A and the new switch you are suggesting as switch B. The NVR has several cameras connected directly into its PoE ports. Switch A and the NVR are connected to switch B and switch B connects to the modem/router.
It means, if I understand correctly, that the NVR will then be processing all camera data via the switches A and B and the router then acts only as a gate allowing my laptop to access the NVR's network.

As for the "CAM Offline Alarm"...... I have increased the dBm power of the two antennas bridging the house and switch B 100m away and so far I have no "CAM Offline" alarms. Maybe that was the problem. I'll know for sure in a couple of days if I have no further alarms.

Re factory resets..... after doing the firmware upgrade I did a factory reset but I did not do one before doing the upgrade. Is not doing a factory reset prior to a firmware upgrade a definite problem?

 

[TonyR]

The "CAM Offline Alarm" alert has only started since I did a firmware upgrade on the two 5442 cameras on the switch 100m away.

It may have been beneficial to have read that little tidbit of info in your first post....IMO.

 

[gregip]

Update.... the increased dBm power of the two Ubiquiti antennas did not fix the "CAM Offline Alarm" issue. Tomorrow I'll redo the firmware upgrade on the two 5442 cameras.

The NVR/monitor GUI Camera List page shows the "Remaining Bandwidth / Total Bandwidth" as 100Mbps/168Mbps.
The two 4MP 5442 cameras connected to the switch 100m away (and then via the Ubiquiti wireless bridge to the modem/router in my office) plus eight other 6MP cameras and one 8MP camera connected to the NVR ports in my office make up the entire NVR network. Nothing else has access to or is connected to it. Nearest neighbours are 100m away from the modem/router.
Can anyone more clever than me deduce from this what the Mbps traffic is that is going through the modem?

 

[wittaj]

It looks like at the time you pulled this, the cams are pulling 68Mbps, so that is what your router is trying to process of a 24/7 never buffer data stream. Keep in mind even if they are set to CBR, you will still see fluctuations on this based on motion, etc.

 

[gregip]

...the cams are pulling 68Mbps,

Yes I wondered if that was the case but that is for all cameras. Since only the two 4MP 5442 cams were going through the router to the NVR I guessed the router was only processing (2x4)/((2x4)+(8x6)+8)MP = 12.5% x 68Mbps = 8.5Mbps. The 8.5Mbps seems minimal to me but I'm far from an expert.
Are these calcs a good enough approximation and would you consider the 8.5Mbps to be too much for the router to handle?
By the way, the cams were going offline when there was no motion at all - no people, no cars, no wind, no leaves, no shadows, no animals....
I like your idea of the extra switch wittaj but I have to buy it and get it shipped to me so that will take a few days. In the meantime I'll redo the firmware upgrade.

 

[gregip]

An update.... the firmware redo did not improve the CAM Offline issue. I did reduce the channel width from 40Mhz down to 20Mhz but it is unclear if that helped.
For the first time in two months only one camera went offline today. It has always been both cameras. The last time the two cameras went offline was about one week ago. Still no apparent reason for why the cameras go offline.