Hikvision PoE Port 1 dropping packets ? OR an uplink port for the built-in hub?

[Slash5k1]

Hi,

Just purchased a Hikvision NVR (DS-7608NI-I2/8P) with 2 DS-2CD2387G2-LSU/SL cameras and to my surprise everything was pretty simple to setup.

Upon a quick play I noticed that 1 camera was pretty much in sync with me waving my hand in front of the lens while the other was sometimes in sync and then other times half a second or more behind.

Long story short of playing around with settings I found that if I moved intermittent camera that was out of sync to another PoE port that it would be in sync with the other camera.

My question to the gurus out there is, is there a known issue, bug, feature in how Hikvision manages / wires up the internal switch for port 1 to be behaving like this OR have I stumbled upon a hardware fault?

 

[ludshed]

Try putting the other cam in port one and see if it does it as well.

 

[Slash5k1]

Try putting the other cam in port one and see if it does it as well.

that’s how I found there was something night right with the port…

initially I changed Ethernet cables after trying settings and then resetting everything to default.

I then swapped the camerasaround thinking maybe it’s a dud cameraonly to find the camera that was in sync was now out of sync.

I then tested the other ports and found both cameras operated in sync… which lead me here to think … what’s up with port 1?
Not knowing if it’s a hardware switch or a software switch or is the NVR doing something under load and port one doubles up as something else, I thought I would ask the question before sending the NVR back as we head into Xmas.

my gut tells me it’s a hardware fault and to ignore port 1 as the site will only ever see 4 (maybe 5) devices but then I think - I only just bought this…

anyone else experience this? Maybe on other ports?

next test is to plug the laptop in to each PoE port and see what happens when I flood them with packets …

 

[Slash5k1]

Well the plot thickens ...

I setup 2 machines to run iperf3 for some testing and found while each machine was plugged into ports between 2 and 8 with my 2 cameras on a port between 2 and 8 I could overload the switch with video freezing or dropping out completely but if I moved the server side to port 1 and try to the flood the switch with iperf there was no impact to the video streams at all.

its almost like ports 2-8 are setup to multicast and port 1 is doing something else.

Im starting to think this isn't a hardware issue / fault but perhaps there is more going on with port 1 then whats been documented ?

testing topology below:

• DS-7608NI-I2/8P (V4.60.005 build 220927)
• DS-2CD2387G2-LSU/SL (V5.7.2 build 220713)

This actually could be a good thing for the topology I was thinking of building where I have a switch plugged into one of the NVR PoE ports (will use port 1 now ) and another in the NVR LAN port running on two seperate VLANs so I could still access the cameras directly and wire in the intercom and indoor station (without the need of another PoE switch) to the NVR PoE switch as shown below:



If anyone has any insight on what I have found with port 1 it would be greatly appreciated.

Cheers!

 

[Slash5k1]

Just a thought… maybe the built-in 10/100 switch ain’t a switch but instead a hub (hence why I could kill the camera streams with iperf traffic) with port 1 as an uplink port acting more like a switch port.

Would make sense if that was the case as you could create quite the broadcast storm across the devices connected to the built-in ports of the NVR (potentially killing the video streams) if you blindly added a switch to it (like I was thinking of doing) with every packet coming from the upstream network being forwarded to every port.

I could get some TCP dumps going to test the theory but I’m happy to conclude that all ports work, all ports provide PoE and if the cameras were already mounted and setup outside I wouldn’t have even picked up on the slight delay for the camera on port 1.

For those thinking the built-in hub / switch on the NVR is rubbish why don’t you buy a separate PoE switch for the cameras, intercom and indoor monitor then configure each camera to the NVR over the LAN port… problem solved… you are probably right but then I would have to buy another PoE switch and I don’t want to spend the money.