How to disable IGMP in Raspbian

linux-networkingmulticastraspbian

I am writing testcases for the IGMP and MLD implementation of a network switch. Those testcases run on Raspbian. However, Raspbian seems to regularly send IGMP reports/queries of its own, which interfere with my testcases. How can I disable those packets, either globally or for a given interface?

I have seen this answer, but had no luck in figuring out which process generates the IGMP traffic. I do not have any applications installed that require multicast groups, to the best of my knowledge.

Because I need to send and receive IGMP with Scapy for the testcases, just blocking IGMP in the firewall is not an option.

Here is the traffic in question:

pi@raspberrypi204:~ $ sudo tshark -i any -Y igmp
tshark: Lua: Error during loading:
[string "/usr/share/wireshark/init.lua"]:46: dofile has been disabled due to running Wireshark as superuser. See http://wiki.wireshark.org/CaptureSetup/CapturePrivileges for help in running Wireshark as an unprivileged user.
Running as user "root" and group "root". This could be dangerous.
Capturing on 'any'
[...]
196  62.189350 192.168.178.202 -> 224.0.0.22   IGMPv3 64 Membership Report / Join group 224.0.0.252 for any sources / Join group 224.0.1.12 for any sources
197  62.344484 192.168.178.201 -> 224.0.0.22   IGMPv3 62 Membership Report / Join group 224.0.0.252 for any sources
198  62.356118 192.168.178.201 -> 224.0.0.22   IGMPv3 62 Membership Report / Join group 224.0.0.252 for any sources
199  62.357405 192.168.2.206 -> 224.0.0.22   IGMPv3 62 Membership Report / Join group 224.0.0.251 for any sources
201  62.361857 192.168.178.201 -> 224.0.0.22   IGMPv3 62 Membership Report / Join group 224.0.0.252 for any sources
206  62.384387 192.168.178.201 -> 224.0.0.22   IGMPv3 62 Membership Report / Join group 224.0.0.252 for any sources
[...]

I am using:

pi@raspberrypi204:~ $ lsb_release -a
No LSB modules are available.
Distributor ID: Raspbian
Description:    Raspbian GNU/Linux 8.0 (jessie)
Release:        8.0
Codename:       jessie

Best Answer

Group 224.0.0.252 is for LLMNR and 224.0.0.251 is for mDNS. One guess is that it the avahi-daemon generating it, you might try uninstalling it to see if the traffic stops.

But since you are using this to run tests, I suggest you look for a small VM that you can run, that way you will have a much more control over what is on your testing environment, and it is easy to replicate to another machine without risking running to this kind of problem again.

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