Linux IPv6 routing strange behaviour

Erik Muller erikm at
Wed Aug 14 21:07:11 CEST 2013

On 8/14/13 14:30 , Max Tulyev wrote:
> OMFG 8-|
> What is the soultion? There are *MILLIONS* of flows in the backbone...

I'd try increasing the routes max_size limit as a first step.  If you're 
running heavy traffic and/or full routes through a linux box, you're going 
to need to do some tuning and trial-and-error testing - a lot of default 
parameters are not optimized for a router role.
You may also want to decrease the gc_interval, and poke around at some of 
the other knobs there.


> On 14.08.13 21:10, Hannes Frederic Sowa wrote:
>> On Wed, Aug 14, 2013 at 08:00:49PM +0300, Max Tulyev wrote:
>>> On 14.08.13 13:59, Hannes Frederic Sowa wrote:
>>>> If a packet is delivered to a destination, we clone the routing entry and
>>>> reinsert it back into the fib trie.
>>> Does it mean the original route is keept or deleted?
>>> Does it do for EVERY packet, i.e. EVERY packet generates a (temporary)
>>> FIB entry???
>> Every flow does generate a FIB entry, yes. As soon as the fib entry is
>> installed it will get reused or discarded as soon as the GC decides so.
>> Greetings,
>>    Hannes

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