Camera Subnet

[nothappy]

I have a NVR-87400 and all the camera's are set for a subnet of 172.16.25.x/24, my business network is 172.16.x.x/16. I can't change my business network and would like to change the subnet of the cameras to something like 192.168.1.x/24. Technical support was not very helpful as I had problems explaining that the NVR can not route packets correctly if the WAN and LAN subnet of the box overlap. I don't want to buy another box to put in front of the NVR just to translate the IP addresses, the NVR system should provide this simple option in the software. Has there been new firmware that allows this, or did I just miss it in the software UI? If anybody could help I would appreciate it.

 

[mat200]

I have a NVR-87400 and all the camera's are set for a subnet of 172.16.25.x/32, my business network is 172.16.x.x/16. I can't change my business network and would like to change the subnet of the cameras to something like 192.168.1.x/32. Technical support was not very helpful as I had problems explaining that the NVR can not route packets correctly if the WAN and LAN subnet of the box overlap. I don't want to buy another box to put in front of the NVR just to translate the IP addresses, the NVR system should provide this simple option in the software. Has there been new firmware that allows this, or did I just miss it in the software UI? If anybody could help I would appreciate it.

Welcome @nothappy

Typically NVRs with PoE ports create their own subnet for their PoE ports, and it is just the WAN port ( which you connect to your LAN ) that you need to configure so that you can view the video feeds from your LAN.

Question(s):
Are all the cameras connected to the NVR PoE ports?

 

[nothappy]

Yes, that is what the problem is. The NVR is configured for a subnet that conflicts with my network. For example, my network gives the NVR an IP of 172.16.4.10. The NVR creates subnet 172.16.25.x for the cameras that are plugged into the LAN/PoE ports of the NVR, so when I plug in camera1 it gets 172.16.25.2, lets say. So now the NVR has a 172.16.4.10/255.255.0.0 and the LAN ports of the NVR have 172.16.25.x/255.255.255.0 with camera1 having 172.16.25.2.

The OS of the box will not know how to route a packet in this case, because a network packet matches two routing ports, so it fails to route the packet, therefore packets enter but they don't leave. I use to work for a company programming set top boxes, and this was one of the problems I had to fix for them, it is easy to detect a subnet collision and inform the user they need to change the subnet of the LAN side of their box. This should always be a requirement for any NAT type box that is going into another network, as you don't know what the customer's network will be configured like.

I was just hoping the NVR UI would provide a way to change the LAN/PoE subnet....or someone knew of a software revision where this is possible. Or someone knows how to get shell access to the box so one could do it manually.

 

[alastairstevenson]

In the Hikvision NVRs there is no facility to configure the camera subnet in the web GUI, but it can be done in the VGA / HDMI interface. Is that something you've checked for this NVR?

 

[nothappy]

I've never checked the Web GUI, unfortunately Swann's VGA GUI doesn't have an option that I can find for it.

 

[alastairstevenson]

Optimistic, but :
Assuming you can configure a camera's IP address to one that does not overlap the LAN - does the NVR find that camera when it's connected to an NVR PoE port?

 

[zero-degrees]

I'm curious where and how you are seeing a subnet collision or if you are just making assumptions. The NVR's typically do NOT pass any packets or traffic out past the WAN to LAN port connection - they are designed to keep all video traffic segmented at the NVR, so, where are you seeing an IP conflict occur - do you have devices (PC's, Servers, etc) reporting an Ip conflict? Also, what packets would you be trying to pass back though the NVR as your NVR's IP takes all primary responsibility and control function of all items connected to the NVR POE ports and all video is recorded locally at the point - no video data is moving across your entire network to a networked recorder located on a different switch. IMO unless I am missing something, you are making an issue out of something that may not be an issue... Sidenote - Buy big box retail system, get big box retail limitations.

 

[nothappy]

It's not an IP conflict, it's a subnet conflict. An IP conflict would be reported on another PC, running windows. A subnet conflict is only going to show up on the device itself. When you have a subnet conflict the box can't even answer a simple ping, at first I didn't know the IPs of the cameras and simply couldn't see the box on the network. Running wireshark and other network analyzers I could see the packets making it to the box, then after poking around on the GUI I noticed the IPs of the cameras, that's when I immediately knew the issue. If I move the box behind a NAT that uses 192.168.1.x it works. However, as I stated in the first post I don't want to have to use another box. The NVR is going to sit in a rack mount case that doesn't have room for another box, and I don't want to have the NAT latency in the link. I'm running Linux on most of my machines, and I'm willing to bet the box is running Linux as well and the LAN subnet should be a simple thing to change.

On your sidenote, after I encountered the problem and hitting the net, I came to that same conclusion. I should have bought individual components and built the system up, seems the standalone NVRs are a lot more configurable. However, a friend of mine showed me the All In One Swann system and given the price I thought it would fit the bill. Just had no idea the GUI configuration of the system would be so limited. I guess I should have known it would be like the BIOS configuration of a motherboard bought separately versus a built system by Dell where they just let you set the date.

I took the thing apart since it's way out of warranty and noticed a couple of places there could be a debug header on the board. I wish I could find someone online that knew more about it, but unfortunately no one is messing with it on that level. I guess I'll probe it out and see what I see. I was just hoping that Swann would eventually provide the LAN configuration in the GUI.

Thanks for the responses.

 

[mat200]

It's not an IP conflict, it's a subnet conflict. .. If I move the box behind a NAT that uses 192.168.1.x it works. ..

Hi @nothappy

Help me understand this better, are the following correct?

1) Model Swann NVR-87400
2) LAN default for Swann NVR-87400 = 172.16.25.x/32 ( or was this your setting you configured on the NVR ? )
3) WAN default for Swann NVR-87400 = 192.168.1.x/32 (? this is what Swann expects to be used.. )
4) The GUI you are using is the On Screen Display ( OSD ) GUI? ( as in hook a monitor to the NVR ) and not the webgui.
5) LAN settings of the Swann NVR-87400 are not fully available via the OSD GUI.

Have you checked for updated firmware?

it appears to be a Hikvision OEM kit from what I can tell....

 

[IAmATeaf]

Looking at the manual for this model it doesn’t look like the subnetwork of the cams can be changed so you’re kind of stuck.

The manual for the Hik equivalent states:


The Internal NIC IPv4 Address is assigned to the cameras con- nected to the NVR and cannot be changed.

 

[IAmATeaf]

What I would do is ensure that the cams sit on their own separated cabling which should be easy enough to do if you have structured cabling and if you have later 2/3 switches then even easier so separate them using VLANs.

 

[nothappy]

Hi @nothappy

Help me understand this better, are the following correct?

1) Model Swann NVR-87400
2) LAN default for Swann NVR-87400 = 172.16.25.x/24 ( or was this your setting you configured on the NVR ? )
3) WAN default for Swann NVR-87400 = 192.168.1.x/24 (? this is what Swann expects to be used.. )
4) The GUI you are using is the On Screen Display ( OSD ) GUI? ( as in hook a monitor to the NVR ) and not the webgui.
5) LAN settings of the Swann NVR-87400 are not fully available via the OSD GUI.

Have you checked for updated firmware?

it appears to be a Hikvision OEM kit from what I can tell....

1) correct
2) correct (default nothing on the NVR that I see allows me to change this)
3) With the NVR WAN getting a 192.168.1.x/24 address things are fine. However my network runs a 172.16.x.x/16 subnet, which I can't change.
4) correct, OSD GUI with monitor on VGA port
5) correct, can't find anything

I have downloaded a newer firmware, but I haven't installed it yet. I was hoping someone would answer the question before I installed it. That way, if I have to go in the back door I want to have the older firmware on the box in case someone found a vulnerability that is fixed in the newer version. Configuring the LAN subnet is kind of a big feature to leave out of the release firmware then introduce it later, but it's possible.

 

[nothappy]

What I would do is ensure that the cams sit on their own separated cabling which should be easy enough to do if you have structured cabling and if you have later 2/3 switches then even easier so separate them using VLANs.

The cams are on separated runs, however putting something between the cams and the NVR I don't think will help. Putting something in front of the NVR before my switch yes, VLAN, NAT, I just don't have the room for that other box to configure something like that, and I don't want to because I'm still a little angry this box doesn't allow for any consumer network configurations. I guess another option for that matter is to take their box and use it for target practice and buy another box that supports the cams and the configuration options I want, or build a Linux box to do the job. But hell if I had that much free time, I would have done that from the beginning.....but I don't.

 

[K175un3]

The POE ethernet ports and the ethernet port are on seperate controllers nothappy.

I believe it is possible to ping the cameras, as with some manufacturers NVR's it is possible to access and configure the attached cameras through the NVR. But I'm still learning a lot about IP CCTV systems from moving from the older BNC types.

And may we ask where you're based please? As we may be able to provide other sources of hardware for you for future reference.

 

[IAmATeaf]

Either accept the you’ll have to allocate the .25 net to the CCTV system, you’re using /16 so you have a massage range of sub networks or return the system as not being compatible.

 

[nothappy]

Returning it is not an option since it's been too long, and yea I could reconfigure my whole network and allocate individual /24 networks around the .25, but I don't want to, because I like how I have the vendor pools setup now in the DHCPd and I don't want to change it....I'd rather waste my time trying to bend their product to my will instead of me having to bend to their limitation.

K175un3, I'm in the US, Texas....thought it showed my location.

Anyway, thanks for the responses, figured I'd see if anybody knew of a way to make it work, guess I'll dig deeper.

 

[IAmATeaf]

You only need to reconfigure devices on the same sub network as the CCTV not the entire?

 

[nothappy]

Maybe I don't understand your solution.....here is a little more on how my network is configured.

Everything plugs in to one switch.

Internet--------Gateway------------SWITCH----------NVR--------Cams
                172.16.0.1         172.16.x.x                 172.16.25.x

In order for the NVR to be happy the NVR would need to be given a /24 address and for it to route packets it would need to be on the 172.16.0.x subnet, e.g. 172.16.0.10/32, so the default gateway would be 172.16.0.1/24. I don't think that works. Lets say my PC, 172.16.3.10/16 sends a packet to 172.16.0.10/16...not sure the NVR will see that packet since it's subnet is 172.16.0.10/24.

It's been a while since I've done some routing work, but I think I remember that scenario doesn't work, but I'll give it a try. If that's not what you meant, sorry for the yapping, could you please explain it a little better. Thanks.

 

[Hammerhead786]

What are the subnet masks for each network? Anything that follows the / indicates the number of network bits used i.e. /32 means you are using 32 bits for the network portion of the address and 0 bits for the host address.

 

[nothappy]

What are the subnet masks for each network? Anything that follows the / indicates the number of network bits used i.e. /32 means you are using 32 bits for the network portion of the address and 0 bits for the host address.

The network is 172.16.x.x/16 or 255.255.0.0
The NVR Cam subnet is 172.16.25.x/24 or 255.255.255.0