Orbi RBK850 in AP mode can't connect to satellite

[schadan]

Hi, seems that my problem is not new but I was not able to find a working solution: I'm running a Orbi RBK850 together with two RBS850 in my home network. I've done first the setup of the whole system in router mode with successfully syncing wireless both satellites, then powered off both satellites, switched the RBK to ap mode & after successfully restarting the RBK switched on the satellites. The RBK is getting his ip address now from an isc dhcp server on a RASPI, the RBS should do so as well - I've identified the related mac addresses & created reservations on my RASPI. On the RASPI I can see that the dhcp reservation is successfully been assigned to my RBK, but when restarting the satellites I can see that the satellites are pulling again & again via dhcp their ip addresses (which are acknowledged by the dhcp server but somehow maybe ignored by the satellites?). Furthermore I can do whatever I want but the satellites can't no longer sync wireless with by RBK - neither pushing the sync button on both RBK and satellites nor powering off & on the satellites has helped. Both satellites show magenta led ring colour.

Cabling the satellites to the RBK (ethernet backhaul) have synced them (blue led ring) but a few seconds later the led ring colour again switched back to magenta & the satellites were ignored by my client systems.

Does anyone else has an idea how to solve this issue? After setting up the whole system the 6th time I have no further idea...

Thank You

[schadan · Accepted solution]

Hi,

the problem is solved 🙂

A simple cause had a big effect - I could see in the pfsense fw logs that outbound icmp was blocked - seems that the RBK is pinging to some cloud front systems regularly to see whether it has an internet connection. After enabling it it worked like a charm, the gui shows internet connection & I was able to sync both satellites.

Now I only have one small (not really urgent) problem left & that is that I'm getting (only on the RBK) a http 500 when connecting to the WebGUI via DNS name in the URL - using the ip address instead is working. But for this I will open another thread.

Thank You very much for Your help, really appreciated 🙂

[FURRYe38]

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@schadan wrote:

Hi, seems that my problem is not new but I was not able to find a working solution: I'm running a Orbi RBK850 together with two RBS850 in my home network. I've done first the setup of the whole system in router mode with successfully syncing wireless both satellites, then powered off both satellites, <I would leave the RBS ON and synced to the RBR when you go to switch the RBR to AP mode) switched the RBK to ap mode & after successfully restarting the RBK switched on the satellites. The RBK is getting his ip address now from an isc dhcp server on a RASPI, the RBS should do so as well - I've identified the related mac addresses & created reservations on my RASPI. On the RASPI I can see that the dhcp reservation is successfully been assigned to my RBK, but when restarting the satellites I can see that the satellites are pulling again & again via dhcp their ip addresses (which are acknowledged by the dhcp server but somehow maybe ignored by the satellites?). Furthermore I can do whatever I want but the satellites can't no longer sync wireless with by RBK - neither pushing the sync button on both RBK and satellites nor powering off & on the satellites has helped. Both satellites show magenta led ring colour.

I also set the RBR for a static IP address for AP mode on the RBR, i.e. 192.168.#.85 on mine when in AP mode. This IP address is out side of a default DHCP IP address pool I use of .100 to .200. 

Cabling the satellites to the RBK (ethernet backhaul) have synced them (blue led ring) but a few seconds later the led ring colour again switched back to magenta & the satellites were ignored by my client systems.

Are the RBS directly connected to the back of the RBR or is there a LAN switch in between? 

What CAT# LAN cable are you using between the RBR and RBS? CAT6 is recommended. 

Does anyone else has an idea how to solve this issue? After setting up the whole system the 6th time I have no further idea...

Thank You

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[CrimpOn]

It would be helpful to know:

• What ISP device is the Orbi router connected to?
• Where is the Raspberry Pi located? i.e.
  • Is it "upstream" of the Orbi router? perhaps connected to the ISP router?
  • Is it connected to the Orbi router?
• When in router mode, which device was supplying the WAN IP to the router?
  • ISP router, or
  • Pi

I agree with @FURRYe38 , when switching the Orbi from router to AP mode, there is no need to power off the satellites unless the changeover is complicated.  such as no Pi in router mode, then use Pi in AP mode?  Maybe changing router IP subnets?

Perhaps there some confusion over LAN subnets?  When in router mode, the Orbi LAN subnet must be different from the WAN iinterface subnet.  i.e. if the Orbi router receives 192.168.xx.yy as its WAN address, then the LAN subnet can be any private subnet that is not 192.168.xx When in Access Point (AP) mode, the router WAN interface and all the devices attached to the LAN side are all in whatever IP subnet is being used by the upstream DHCP server.

[schadan]

Hi, the ISP device is a Fritzbox 7490. The RBK is connected via LAN port to a switch -> Fritzbox. Connecting the RBK via WAN port was not working and causing a flickering WAN connection. The RASPI is connected via the mentioned switch.

Regarding the satellite connection I tried the ethernet backhaul via direct connection to a LAN port on my RBK, but I‘d really prefer to have a wireless backhaul.

[FURRYe38]

The RBR in AP mode has to be connected to the host router using it's WAN port while in AP mode. 

What is the brand and model of the switch being used? 

[CrimpOn]

There is probably a reason for deploying DHCP on the Pi rather than using the Fritzbox 7490 DHCP feature?

(what with ISC DHCP being End of Life and all) https://www.isc.org/dhcp/ 

So this is what it looks like?

[schadan]

Hi, yes, the diagram fits quite well. Yes, I know about the EOL of isc-dhcp-server. The switch is a tp-link tl-1008 unmanged desktop switch.

As described connecting the RBK850 via WAN doesn‘t work unfortunately. What would be the reason why connecting via WAN port when the RBK is in ap mode would make sense? Thanks.

[CrimpOn]

My first thought is that Netgear probably designed the router to "know which port" leads to

• The DHCP server that assigns an IP to the WAN port. (my guess is this is the WAN port itself.  If the WAN port is not connected, then what IP does it get?)
• Where the "rest of the network is" (i.e. everything not connected to the Orbi LAN)

I have not personally conducted any sort of experiment that involves not connecting an Orbi using the WAN port and having the DHCP server appear to be "on the Orbi LAN".  It would take some effort to monitor both the WAN and LAN ports to see what DHCP traffic appears on all of the ports.  I could, for example, see the DHCP requests from the satellites (which are broadcasts) being sent out every port on the router.  I believe the DHCP server reported getting DHCP requests from the satellites, but not completing the process. (i.e. the satellites did not respond to the DHCP assignments - which are sent back through the LAN port, not the WAN port.

I'm still struggling to understand why not using the Fritzbox for DHCP is essential.

[schadan]

I'm really sorry - I've forgotten to mention one important component: there's a pfsense firewall sitting in between the fritz!box and the remaining parts of my network (I'm an old man ;-). The reason why I have setup the dhcp on my RASPI is that I have to use my RASPI anyway because of pi-hole which I have setup there to block unwanted blacklisted dns requests.

[schadan]

...and btw regarding the WAN port: I've connected the Orbi via the second port - that's the port which can be used as a WAN port aggregation. Somehow it seems to work instead of using the WAN port itself - the mac address differs only by one digit. For me it looks like at least these two ports are operated by the same nic.

[FURRYe38]

Is the front LED OFF when using the 2nd LAN port over or is it ON and PINK? 

Reason why the WAN port needs to be used is for the main connection and the status of the front LED. 

What is the CAT# lan cable between the RBR and Firewall device? 

Possible the firewall device is blocking proper data flow. 

Try the RBR directly connected to the Fritzbox with out the firewall in the middle using the RBR WAN port. 

[schadan]

The front led is off. But I think the (possible) connection of the WAN port is another topic - I'm still wondering why the satellites can no more connect to the RBK via wireless (or via ethernet backhaul only by the explained behavior).

[FURRYe38]

I would try the WAN port again and this time, don't have the firewall in the mix. Go from the ISP router to the RBR using the WAN port on the RBR. You might even start back from step one with the RBR in router mode and get the RBS connected here, then configure AP mode on the RBR, leaving the RBS ON. 

AP mode works on the 850 with using the WAN port. I just had mine in this configuration last month. 

[schadan]

Hi,

OK, I did the following (tested with Fritzbox, RBK850 and one RBS850):

1) connected my RBK850 (second port) with my Fritzbox (LAN port no. 4) and rebooted the RBK. Internet access via WLAN works. Satellite is not syncing wireless. I connected then the satellite via cable to my RBK, it was syncing & on the Fritzbox I could see that an ip address from my Fritzbox was successfully assigned, but when I unplugged the cable again the connection was lost and even when waiting some minutes it was not reconnecting.

2) connected my RBK850 (WAN port) with my Fritzbox (LAN port no. 4) and rebooted the RBK. Internet access via WLAN works. Satellite is not syncing wireless.  I connected them the satellite via cable to my RBK, it was syncing & on the Fritzbox I could see that an ip address from my Fritzbox was successfully assigned, and now the difference to 1): when I unplugged the cable from the satellite it took a few minutes but at the end the satellite was syncing successfully with the RBK and on both the Fritzbox again and the Orbi WebGUI I could see the assigned ip address (and was able to login via browser).

So I would conclude that the dhcp requests (in this test of course they were managed by the Fritzbox and not by my RASPI) will only be forwarded by the RBK to the satellites indeed when the RBK is connected to my network via WAN port.

As next step I have to analyze why the connection behind the pfsense is not completely working (status in the Orbi WebGUI shows good when the RBK is connected via WAN port directly to my Fritzbox & fails when connected to my pfsense and if there is some issue with my isc-dhcp-server.

Do You perhaps know any concrete configuration requirements specially for the dhcp server which needs to be considered? And regarding the WAN connection do You perhaps know if there are some special port openings needed for the RBK?

Thank You.

[CrimpOn]

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@schadan wrote:

some special port openings needed for the RBK?

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(Assuming port openings is in reference to the pfSense Firewall.)

Port forwarding pertains only to incoming connections.  Any device on the network can open connections to the internet.

If the Orbi is in Access Point (AP) mode, its internal firewall is not enabled.  Connections can be made from and to any device on the network (including the pfSense).  In addition, Ethernet broadcasts will go to every device on the network.  Connections from the internet to internal devices are monitored entirely by pfSense.  For example, if a web server on a local device needs to be reached from the internet, then pfSense must forward the appropriate port (usually 80 or 443) to that device IP.  Of course, the pfSense Firewall will only receive incoming connections if the Fritzbox has port forwarding rules in place.

If the Orbi is in router mode, then the internal firewall is enabled and rejects all connections from the internet unless a Port Forwarding rule has been enabled by the user.  This will make the situation a bit more complicated. i.e.

• The Fritzbox will have to forward the required port to the pfSense IP.
• The pfSense will have to forward the required port to the Orbi router IP
• The Orbi router will have to forward the required port to the internal web server IP.

This can be done.  I have deliberately set up three routers in a chain. i.e.

• internet modem to router 1
• router 2 connected to router 1
• router 3 connected to router 2
• user device connected to router 3.
• open a web server on user device
• forward port 80 through router 1 to the IP of router 2
• forward port 80 through router 2 to the IP of router 3
• forward port 80 through router 3 to the IP of the web server.

But, geez. what a complicated mess!

This is why the consensus on the forum is "unless you have zero need for any connections* from the internet to local devices, have only one router in the network."

* This means no need to access anything on the network from the internet:

• No media servers
• No web servers
• No internet game hosts
• No OpenVPN
• do internet search for "Double NAT" for more examples

If this really is the case, then it doesn't matter how many routers there are

[schadan · Accepted solution]

Hi,

the problem is solved 🙂

A simple cause had a big effect - I could see in the pfsense fw logs that outbound icmp was blocked - seems that the RBK is pinging to some cloud front systems regularly to see whether it has an internet connection. After enabling it it worked like a charm, the gui shows internet connection & I was able to sync both satellites.

Now I only have one small (not really urgent) problem left & that is that I'm getting (only on the RBK) a http 500 when connecting to the WebGUI via DNS name in the URL - using the ip address instead is working. But for this I will open another thread.

Thank You very much for Your help, really appreciated 🙂

[FURRYe38]

Glad you got it working. Be sure to save off a back up configuration to file for safe keeping. Saves time if a reset is needed.
https://kb.netgear.com/000062080/How-do-I-back-up-the-configuration-settings-on-my-Orbi-WiFi-System
Enjoy. 📡