OK, there are a couple of things going on here that I don't understand. First, why should a DaHua camera on a DaHua NVR have to be manually switched from Private protocol to ONVIF? Second, why doesn't the NVR save that information anywhere. If the camera or the NVR are rebooted, the protocol information isn't saved and it has to be manually changed again.
Now, I connected my laptop that I had to pry from my wife’s cold (not) dead hands to a port on the NVR. From there I can access the camera's web page and I have access to the full array of configuration options, including all of the different resolutions up thru 2304x1296. So while there, I changed the ip addressing from DHCP to static, keeping the original IP address of x.x.x.129. The ARP/PING was already enabled so as a check I disabled it.
Then, just to make sure I would have a clean start, I rebooted the NVR. I waited and waited but the camera never did come online again. I logged back in to the cameras web service using the laptop and changed the ARP/Ping back to checked, and saved the settings. Rebooted the NVR again and this time the camera came back online. For THIS camera at least, ARP/PING has to be checked.
BUT! Even though I set the camera's IP address to a static x.x.x.129, the NVR still changed it to x.x.x.69. What the heck? I must have screwed it up, so back to the laptop and login to the camera. It did indeed show x.x.x.69, but still a static address. I went through the process again setting the camera IP back to x.x.x.129, saved, saved again, and rebooted the NVR again. This time the IP address was changed to x.x.x.77. Subsequent attempts seem to indicate the NVR is finally happy with x.x.x.77.
And another BUT. After all of this, the camera's settings are essentially still not available, and no resolution higher than D1.
I just noticed two things neither of which is probably relevant. First, some time ago I had changed the TCP port in the camera from the DaHua default of 37777 to the Lorex default 35000 to match the Lorex NVR I was using. I didn't have to but I did. Thinking that maybe the DaHua NVR didn't recognize the Dahua camera because it was on the wrong port, I changed the port in the camera's network settings back to 37777. Sadly, nothing changed. The second thing is that when I looked at the settings for the camera shown in the Modify panel when changing the protocol, the TCP Port number is 13, and I am unable to change it. Port 13 is the Switch port the camera is attached to, not the TCP Port which should be 37777. This is probably not relevant because the other Lorex camera attached to this NVR also says the Physical port number instead of the 35000 TCP Port and it works perfectly. Maybe just a bad translation somewhere from Chinese to English.
Wayne