I do have multi camera connection on my Dahua and Amcrest NVRs. They can support up to 4 and 8 channels depending on the NVR build type.. Then there are some NVRs like my 5232-16P NVR that has the ability to turn the switch into another switch on my network and connect cameras and other devices on the POE ports of the NVR that then uses my Routers IP POOL..
So when it comes down to setting up something there are some cases where the NVR will only push 1 IP per port. So in that case you will want to setup your cameras with your Switch port IP before you connect the camera to your Switch.. for your first IP and the second camera setup to the next IP after what was your first. Then you will have to add the cameras in manually also to the other channels after your connected Port. Like inmy case, 10.1.1.65, 66, 67 and 68. for port connect to 1 and adding in next camera to channel 2 and so on. However that isn't the case on my 4116E-HS Amcrest NVR. The IP address needs to be on the normal local IP range even though the cameras can be found with different IP when doing a search only 1 10.1.1.xx will load all others will fail. Yet with the rest of the cameras on in my case 10.0.0.xx I can load them on ch2, 3, 4. On another NVR it does have to be on the Switch IP.. So not all of them are the same again depends on the Build of the NVR. Also in that camera can't access any of the cameras using Virtual Host. Not even the main connected 1..
What I mean is lets say that is the issue in your case.. If your cameras are not setup already then 1 camera will get an IP however if you setup the camera on your local network to meet the needs of your NVRs switch IP when you connect the camera it will go to the next channel and ignore the idea that it is coming from 1 port..
What was strange on one of my connected cameras I moved from being on my normal Network POE+ Switch to a port on my NVR, It is an Amcrest POE NVR and a Hikvision OEM mini PTZ camera that I made sure to setup with a DHCP setup in the networking so the NVR would give it a new IP address. What was odd is that when I connected the camera it kept the IP address it already had and came up on the NVRs channel it was installed even though the Camera has my normal local network IP range and it is connected to Port 7 on the NVR it is running on channel 4.. I have since moved it to the correct Channel for the PORT it is connected to but strangely didn't and hasn't changed connection IP..
So there is some down side to having only 1 home run for multi cameras on your NVR. IF you were to want to access the cameras over the NVRs Virtual Host access the camera will connect only 1 of the connected devices because it will be the one registered as a POE connected device and the others will not have access that way.. So for me, Clicking the E on ch7 because it sees the camera as my local IP it will only bring up the local IP address, Can't access that camera over Virtual Host because it is seen as a Local device and not a Port Connected Device. Then on channel 1 when I click on the e for that channel it will load but with the 2, 3 and 4 cameras connected to that port if I was to click the e for them it will not load even though they are connected using only 1 cable and registered on the Switch IP it tries to open a direct line to port2 for ch2 and will fail to let me have local access to the cameras that way but I am able to view and record the channels access all things like motion and so on..
For my system Being Amcrest, 1 cable into port 1 works channel 1, 2, 3 and 4 I have in the past done same for port 5 that would be for 5, 6, 7 and 8 but these cameras are in different area and so they have a home run to the NVR.
