From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hannes Frederic Sowa <hannes@stressinduktion.org>
Subject: Re: Re: Route exceptions for IPv6 routes?
Date: Wed, 15 Jan 2014 14:04:54 +0100
Message-ID: <20140115130454.GE19945@order.stressinduktion.org>
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To: Simon Schneider <simon-schneider@gmx.net>
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Hi!

On Wed, Jan 15, 2014 at 01:25:25PM +0100, Simon Schneider wrote:
> thanks for the answer.
> 
> Sorry, I'm not so familiar with the implementation details.
> 
> What are nh-exceptions?

Nexthop exceptions, they store e.g. pmtu information in IPv4.

> I understand the current IPv6 implementation has some performance drawbacks. Correct?
> 
> I'm especially interested in 
> a) support for path MTUs

They are stored in the RTF_CACHED leafs of the routing table.

> b) IPv6 policy-based routing (can I expect the same results from "ip -6 rule" commands that I get from "ip rule" commands?)

Yes, you can. And they have nearly the same implementation overhead.

Additionally you can add routes which match a specific source and handle them
directly, this is a feature only in IPv6:

E.g. ip -6 route add .... from ... via ...

Greetings,

  Hannes