Setting IGMP Version in RedHat 5.1 (Tikanga)

Question

I am running RedHat Version 5.1 (Tikanga). uname -a yields the following version information: [root@bar foo]# uname -a Linux bar 2.6.18-53.el5 #1 SMP Wed Oct 10 16:34:02 EDT 2007 i686 i686 i386 GNU/Linux

I have four machines configured as described above. I am working on an application that makes uses of multicast facilities, and one of the four machines is runniung IGMP version 3. The other machines are running IGMP version 2. It is IGMP version 2 that I want.

I have looked at all of the "sysctl net.ipv4" options, and though some are related to IGMP, none allow me to set the IGMP version. In fact, the output of "sysctl net.ipv4" on the machine running IGMP version 3 is identical to that of the other three machines.

So, it seems sysctl is not the way one sets the IGMP version. Please correct me if I am mistaken.

Would somebobdy in the know mind sharing how I can configure this machine I have to run at IGMP version 2? Thank you!

Answer 1

See the configuration net.ipv4.conf.all.force_igmp_version. It looks like you can force IGMP version 2 by executing sysctl -w net.ipv4.conf.all.force_igmp_version=2.