Re: [v6ops] Interesting problems with using IPv6

Lorenzo Colitti <lorenzo@google.com> Tue, 09 September 2014 10:29 UTC

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From: Lorenzo Colitti <lorenzo@google.com>
Date: Tue, 9 Sep 2014 19:29:13 +0900
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To: Nick Hilliard <nick@foobar.org>
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Cc: "l.wood@surrey.ac.uk" <l.wood@surrey.ac.uk>, IPv6 Operations <v6ops@ietf.org>
Subject: Re: [v6ops] Interesting problems with using IPv6
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On Tue, Sep 9, 2014 at 6:42 PM, Nick Hilliard <nick@foobar.org>; wrote:

> This happened because the switch CPUs were overloaded with mld report
> packets due to end hosts on the extended L2 network replying to MLD
> all-groups queries every 150 seconds.
>

So the switch was configured to send all-groups queries to all hosts, but
did not have the CPU power to process them, and could not, or was not
configured, to rate-limit them.

News at 11: building a network beyond the capabilities of the gear that
runs it will result in failure.

That does not mean the protocol is flawed. ARP could have done the same
thing, and in fact that was a common problem many years ago... except that
these days ARP is usually processed on the fast path and it doesn't matter.