Re: [v6ops] Interesting problems with using IPv6

"Hemant Singh (shemant)" <> Tue, 09 September 2014 10:43 UTC

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From: "Hemant Singh (shemant)" <>
To: Lorenzo Colitti <>, Nick Hilliard <>
Thread-Topic: [v6ops] Interesting problems with using IPv6
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Date: Tue, 9 Sep 2014 10:43:07 +0000
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Subject: Re: [v6ops] Interesting problems with using IPv6
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Agreed.  Just because one vendor’s switch melted an ipv6 network is not enough justification to change protocols.


From: v6ops [] On Behalf Of Lorenzo Colitti
Sent: Tuesday, September 09, 2014 6:29 AM
To: Nick Hilliard
Cc:; IPv6 Operations
Subject: Re: [v6ops] Interesting problems with using IPv6

On Tue, Sep 9, 2014 at 6:42 PM, Nick Hilliard <<>> 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.