Common operational misconceptions
marka at isc.org
Wed Feb 15 22:27:39 CST 2012
In message <4F3C76D5.9040603 at necom830.hpcl.titech.ac.jp>, Masataka Ohta writes:
> Mark Andrews wrote:
> > This doesn't prove that IPv6 is not operational. All it proves is
> > people can misconfigure things.
> How do operators configure their equipments to treat
> ICMP packet too big generated against multicast and
Well you need to go out of your way to get a ICMP PTB for IPv6
multicast as the default is to fragment multicast packets at the
source at network minimum mtu (RFC3542 - May 2003). That's not to
say it won't happen.
As for generation of PTB you rate limit them the way you do for
> Note that, even if they do not enable inter-subnet
> multicast in their domains, the ICMP packets may
> still transit over or implode within their domains.
> Note also that some network processors can't efficiently
> distinguish ICMP packets generated against multicast and
And why do you need to distingish them? You look at the inner
packet not the ICMP source if you want to rate limit return traffic.
> Masataka Ohta
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742 INTERNET: marka at isc.org
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