IPv6 and multicast listener discovery

Mon Jun 7 16:34:07 UTC 2021

Are your links or hosts limited in some way or broadcast domains
of some unreasonable size?  Most of the competent switching or 
managed wireless products will snoop or otherwise handle this 
overhead in a sane manner.  Otherwise this at best would seem to 
be an over-optimization.

>From my days on a giant campus network the current pps rate of MLD
chatter was much lower than the IPX/SAP broadcasts we had from 
20-25 yrs earlier.

Dale

Thus spake William Herrin (bill at herrin.us) on Fri, Jun 04, 2021 at 02:01:19PM -0700:
> Howdy,
> 
> Question for those more versed in IPv6 than I: Is there any harm from
> dropping ICMPv6 multicast listener discovery reports in a network
> which does NOT use any multicast routing (i.e. only uses multicast
> which stays within the local link). I see a LOT of idle node chatter
> in the form of these reports which, of course, flood every station
> since they are themselves multicast. As far as I can tell they are
> used only to tell a multicast router whether to repeat a particular
> set of multicast packets to the instant link. Which in my network is
> -never- because there are no routed multicast packets to be repeated.
> 
> Regards,
> Bill Herrin
> 
> -- 
> William Herrin
> bill at herrin.us
> https://bill.herrin.us/