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Forum Discussion
Orbi 37x and Local Network Control Block (224.0.0/24) multicast
Dear all, I have an Orbi setup (RBE371 and 2x RBE370) that is causing me headaches with LAN multicast. One of my music application leverages multicast against 224.0.0.234 for node/companion ...
The host router carries all traffic he has to carry, i.e intranet/internet traffic.
Host A & B are RPIs or MacOS depending on the tests I carried on.
Host A & B are WiFi connected to the same Orbi kit (being RBR or RBS depending on the tests I carried on)
Host A can communicate with host B in my LAN as well as other hosts in my LAN using many network protocols
Host B can communicate with host A in my LAN as well as other hosts in my LAN using many network protocols
ARP table of host A shows host B MAC address
ARP table of host B shows host A MAC address
Host A and host B can communicate with any Internet host through the FAI router, from which they get their IP address via DHCP
Host A multicast packets sent to 224.0.0.234 are not received by any hosts in my LAN, including host B
Host B multicast packets sent to 224.0.0.234 are not received by any hosts in my LAN, including host A
If Host A & B are connected to the same Netgear switch, itself wired to a RBS, then they can see multicast packets from each other
Host A & B are RPIs or MacOS depending on the tests I carried on.
It appears the test machines have both Ethernet and WiFi network connections, correct?
Bummer that they cannot both be connected with Ethernet to the same Orbi unit (router or satellite)? (not enough Ethernet ports)
If they are both connected with WiFi to the same Orbi unit (router or satellite), does the multicast still fail?
Test machines are not connected to both Ethernet and Wifi at the same time.
I used a Netgear Switch for the Ethernet test (GS108T) to ensure that both nodes were effectively sending/receiving these multicast packets. This switch has IGMP Snooping and Snooping Queriing
When both connected to the same Orbi Unit, multicast to 224.0.0.234 fails.
What is interesting (I just discovered that) is that these multicast packets are received in the Netgear Ethernet Switch that is wired to the RBS.
I have used tcpdump and Wireshark to witness this traffic from both side.
Attached is a drawing of my setup.
.... I have trouble attaching the drawing
Repeating my initial reply as some text had been cut (timeout i guess) - This one is the good one:
- Test machines are not connected to both Ethernet and Wifi at the same time.
- I used a Netgear Switch for the Ethernet test (GS108T) to ensure that both nodes were effectively sending/receiving these multicast packets. This switch has IGMP Snooping and Snooping Quering are disabled.
- When both connected to the same Orbi Unit via WiFi, multicast to 224.0.0.234 fails.
- What is interesting (I just discovered that) is that these multicast packets are received by a host connected to the Netgear Ethernet Switch that is itslef wired to the RBS, but the multicast packets sent from the device connected to the Netgear Ethernet switch are not received by the hosts wifi connected to the same (and other) satellite or router.
- I have used tcpdump and Wireshark to witness this traffic from both side.
Attached is a drawing of my setup (I'm still not able to attach the drawing)
(I'm still not able to attach the drawing)
Forum bug - not clear when/if Netgear will fix it.
You can put it into cloud storage and include a link. (if the link has the file extension, you can also directly add the graphic or pdf from the cloud storage URL).
I need to set my FAI router with IGMP features which does not make sense for this address block.
Although it doesn't seem to make sense, I suggest that you try it anyway.
The Orbi isn't routing, but is instead operating at layer 2 (since you have it set up as an access point). Are the multicast packets that aren't getting through sending to the layer-2 broadcast (Mac address ff:ff:ff:ff:ff:ff)?
I wish I could play with IGMP settings in my FAI router, at least to park this possible root cause even if it does not makes sense, but I cannot act on any IGMP settings.
Yep, Orbi devices in my setup are supposed to operate at layer 2, reason why I don't get why these mcast packets don't go through, or partially go through, like in the ethernet switch acting at layer 2 too.
According to Wireshark capture, the mcast packets to 224.0.0.234 that aren't going through are using dst mac address 01:00:5e:00:00:ea
Note: other mcast packets such as MDNS (224.0.0.251) are going through well and are using the same dst mac root address, i.e. 01:00:5e:00:00:fb
