[145192] in North American Network Operators' Group
Re: Cisco 7600 PFC3B(XL) and IPv6 packets with fragmentation header
daemon@ATHENA.MIT.EDU (Nick Hilliard)
Fri Sep 30 12:39:11 2011
X-Envelope-To: nanog@nanog.org
Date: Fri, 30 Sep 2011 17:38:09 +0100
From: Nick Hilliard <nick@foobar.org>
To: Christopher Morrow <morrowc.lists@gmail.com>
In-Reply-To: <CAL9jLaa7fNkw_GG9_UemR95v-s=Ae2MLPv-ii6NaGvGvPntopg@mail.gmail.com>
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On 30/09/2011 17:30, Christopher Morrow wrote:
> traceroute is really an example of 'packet expired, send
> unreachable'... that, today is basically:
> o grab 64bytes of header (or something similar)
> o shove that in a payload
> o use the src as the dst
> o stick my src on
> o set icmp
> o crc and fire
>
> there's not really any need to do this in the slow path, is there?
there are unconfirmed rumours that icmp ping and traceroute are handled by
hardware on the asr1k. I don't know if they are true. But you're right -
it would be good to support this without resorting to hammering the routing
engine. I don't really like the idea of punters running traceroutes
reducing my bgp convergence time.
Nick
