MTU handling in 6RD deployments

Anfinsen, Ragnar Ragnar.Anfinsen at
Tue Jan 7 15:49:38 CET 2014

On 07.01.14 14:46, "Jean-Francois.TremblayING at"
<Jean-Francois.TremblayING at> wrote:

>In the list of "tricks", you might want to add:
>* Slightly raise the ICMPv6 rate-limit values for your 6RD BR (we do

How many users use your 6rd BR (pr. BR if many)?

>Too bigs remain quite common however...
>#sh ipv6 traffic | in too
>               11880 encapsulation failed, 0 no route, 3829023354 too big
>#sh ver | in upt 
>uptime is 2 years, 4 weeks, 5 days, 4 hours, 3 minutes

How does the rate-limiting (drops) numbers look at your side?

We hit a problem where the default rate-limiting (100/10) where way to
aggressive. Right now, we have reduced it to minimum (1/200), but we still
see some drops. Next step would be to turn rate-limiting off, but from an
operational perspective, it does not taste very good.

Best Regards 
Ragnar Anfinsen
Chief Architect CPE
IPv6 Architect
Netinfrastructure & Communication
Technology and Innovation
Altibox AS 

Phone: +47 51 90 80 00
Phone direct: +47 51 90 82 35
Mobile +47 93 48 82 35
E-mail: ragnar.anfinsen at <mailto:ragnar.anfinsen at>
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