Subnetting IP Cam Email vs. NVR Email

[Scudrunner]

Hi everyone,

Hello from Texas. New to the forum, first time post, but been around networking and cameras for a few decades or so. That's why it was nice to find a board that looks like has a few members who are smarter than the average bear. Tech support had no clue. Insert your own joke here.

So here is my dilemma. Normally we never install an NVR with the integrated switch for this reason. We like for all the cameras to be on the same subnet as the NVR to avoid problems like this as well as some redundancy issues.

The NVR is an Alibi Witness which is a Hik. The cameras are also Alibi at this location.

The NVR has the LAN IP of 192.168.3.200. The gateway is 192.168.3.1. Email works fine from the NVR to send notifications and snapshots to the client.

The problem is that when you get a notification from the NVR, the snapshot is tiny. If you have the cameras send the notifications, you get the full size snapshot that's large. So at our other client locations, when the cameras are on the same LAN subnet with everything else, we just have the camera email the notification pic. Clients love it.

When the cam is behind the NVR however, the cameras are getting an IP of 192.168.254.x.

One would think that in the cam, we would simply set up the subnet mask to 255.255.255.0, put in the DNS, and set the gateway to (guessing here) 192.168.254.1 to allow the email to route to the NVR, which then has it's own routing rules to hand off to the 192.168.3.1 gateway. That doesn't seem to be working. Could the underlying subnet be using a gateway of 254 or 100? I also tried backing off the subnet mask in the NVR to 255.255.0.0.

I feel sure someone here has already fought this so I thought I would ask before fighting it with multiple reboots for too long. Next step is to set up Wireshark and sniff the packets.

Thanks in advance.

 

[Griswalduk]

Although i can't help you with your problem I'd like to welcome you to the forum.

In the meantime don't worry, others will be all over this pretty soon.

 

[Scudrunner]

Thanks. You would know it's always the friend deals that get you. This the one unit we have that is 1600 miles away. We sent it up there and paid to have it put in for a single mom with a psycho ex/stalker issue. What's the old saying? "No good deed goes unpunished?" LOL

 

[alastairstevenson]

One would think that in the cam, we would simply set up the subnet mask to 255.255.255.0, put in the DNS, and set the gateway to (guessing here) 192.168.254.1 to allow the email to route to the NVR, which then has it's own routing rules to hand off to the 192.168.3.1 gateway. That doesn't seem to be working. Could the underlying subnet be using a gateway of 254 or 100? I also tried backing off the subnet mask in the NVR to 255.255.0.0.

You are heading in the right direction to do the needed configuration to allow Hikvision NVR PoE-port-connected cameras to send alert images via email.

What's needed is :
Enable Virtual Host if it isn't already. This implicitly activates the NVR Linux kernel facility to route packets between the PoE and LAN interfaces internally.
Set the cameras default gateway to the NVR PoE interface IP address, usually 192.168.254.1
And best to change the mode of the NVR PoE channel to Manual instead of Plug&Play to stop it changing that gateway back.

And, finally, the piece I think you missed -
Create a static route on the LAN gateway so it knows where to send packets intended for the NVR PoE-connected cameras, something like :
"For network 192.168.254.0/24 (ie subnet mask 255.255.255.0) use <NVR_LAN_interface_IP_address> as gateway", in your case 192.168.3.200

Test it out by pinging the camera actual IP address such as 192.168.254.2 or directly accessing the web GUI before checking out the camera email config.

 

[Scudrunner]

alastairstevenson, You rock!

Thank you. I was there, and I did have the route and address objects set up in the Sonicwall. The part that was missing was Manual vs. Plug & Pray. The cameras won't reply to ping for some reason, perhaps the port, but that's not a big issue. Tracert finds the camera. The GUI resolves to the camera, and most importantly of all, the cameras can now email the outside world.

I'll be raising my next glass of scotch in your honor. Right after the first drink which by tradition in our office is always, "To absent companions."

My only regret is that I won't be enjoying it with you in The Highlands.

 

[alastairstevenson]

A good result, well done!