Orbi router assigning IPs on 2 different subnets

[Spud204]

My Orbi setup consists of the RBR50 with one RBS50 satellite.  My modem is bridged.  The problem I'm having is the router is assigning IPs from two different subnets; 192.168.1.XX and 192.168.88.XX.  The router is configured to the default 192.168.1.XX subnet so I have no idea where the .88 is coming from!?  I've now manually assigned IPs to the correct subnet and that has seemed to fix the connection issues for my existing devices but why is this happening?

Below are details of my troubleshooting adventure (sorry for the long winded post):

Before the most recent firmware update (2.5.0.38), my setup was rock solid with 25+ devices consistently attached.  After the update, wifi connection became completely unstable.  Various devices would connect but have no internet connection.  Reboots of both the devices and the router did not fix it.  One thing that would seem to fix the connection issues is changing the Proxy setting on the device to "auto" which I found completely strange (was just trying anything at this point).

So after reading through the forums about the newest firmware and issues people are experiencing, I rolled back to 2.3.5.30 (where it was rock solid) but continued to have the connection problems.  Did a factory reset as suggested in the forums but that did not help.  Then I noticed several devices on the attached list had IPs assigned to the .88 subnet and confirmed the same devices had no connection.  Rebooting would result in different devices being assigned the .88 IPs, including my Orbi satellite at one point.

I have checked EVERY SETTING and have no idea where this range of IPs is coming from.

[FURRYe38]

What is the Mfr and model# of the ISP modem the NG router is connected too?

Where is this .88 IP address appearing, on the RBRs connected clients page? or on Devices? 

What are these devcies with the .88 IP address on them? 

What all devices do you have connected? Mfr and model #? 

Be sure you don't have any static IP addresses set ON devices. As these may appear on the RBRs connected clients page.

[Spud204]

Thanks for your quick reply.

The modem is a Hitron CGNM-2250.  It has been bridged with wifi turned off.

I'm seeing the devices with the .88 IPs on the Attached Devices page.  The type of device includes iPhones, iPads, Alexa speakers, Windows laptop and the Orbi satellite itself.  The list of devices will change each time I reboot the router.  At one point, the laptop I was using to troubleshoot with got assigned an .88 IP and I could not get access to the router admin page.

I can't confirm right now but I am almost certain none of the devices have any static IPs set on themselves.  I think the changing list of devices with .88 suggests that as well.

[FURRYe38]

Can you confirm that the modem is still in bridge mode and hasn't been configred back to gateway? Seen it were ISPs push FW updates which can cause the configuration to revert back to gateway mode. This would be one possible cause. 

If the modem is in bridge mode fully, here what I would try. 

Turn OFF ALL devices, Including the RBS. Connect 1 wired PC to the RBR and factory reset the RBR. Press the back button for 15 seconds then let go. Once the RBR is ready, walk thru the setup wizard and complete the setup. I would set up the SSID name however don't input your PW that your currently using. Use a different PW for now. You'll change this later. 

After getting the RBR set up, go in and change the default IP address pool size to the following, 192.168.1.100 to .200. Under Advanced/Settings/LAN Setup. I presume you don't have 100 devices online currently.  Save and apply the change. The RBR will reboot. Once back to ready. Go back to the same place and add your PC as a reserved IP address. Save and apply. The RBR will reboot once more. 

Change the PW for the wifi to what you normally use. Save and apply

After the RBR is ready, turn ON the RBS and let it connect. Do the same thing with the RBS and set a IP address reservation here. Save and apply. I would then connect one wired device, or wireless and let it connect. Do another reservation for this device. Graduate adding one device at a time and set a IP address reservation. 

It's possible that you may run into a device that could be causing this .88 address to appear by using this process. The 88 IP address isn't coming from the Orbi. 

Let us know if this helps any. 

[Spud204]

Thanks for suggestions.  I will confirm the modem is still bridged and follow the process you outlined.  I had assumed if a device was getting an IP from somewhere else, it wouldn't show on the Attached Devices list.

I will report back on how things turned out.

[FURRYe38]

Seen strange things and others have reported similar odd IPs showing in the conntected device list on Orbi that originates from else where. 

Hope this will find where its coming from. 

[cptpizza]

Not sure if you figured this out yet, but I have a test lab that I am working on, and just got the Orbi myself this week.   Am a little disappointed that I can't route my lab subnets from within the orbi network.  I have 172.16.x.x, 10.x.x.x, and 192.168.x.x networks in my lab environment.

There appear to be some firewall rules configured on the underlying Orbi linux OS that blocks anything except 192.168.1.0/24 traffic.   I also suspect this would not be supported by Netgear, so if you are concerned about that, I would recommend against this.  I needed it for my studies, and it did the trick for me to allow access.    Hope this helps...

https://vmexplorer.com/2019/07/23/2055/

Another thread in this community also mentions a similar situation.

https://community.netgear.com/t5/Orbi/Static-Routing-and-NAT-iptables/td-p/1270184

Hope this helps, even if this is a couple of weeks late.