Setting sensible max-prefix limits

Lars Prehn lprehn at
Wed Aug 18 11:17:00 UTC 2021

On 18.08.21 12:36, Saku Ytti wrote:
> On Wed, 18 Aug 2021 at 12:36, Lars Prehn <lprehn at> wrote:
>> As I understand by now, it is highly recommended to set a max-prefix
>> limit for peering sessions. Yet, I can hardly find any recommendations
>> on how to arrive at a sensible limit.
> You are missing two important questions
> a) should I apply it to before or after policy
> b) what should I do when it triggers, should I reset or stop accepting new

When I read through [1] earlier today, I had the feeling that these 
question rather strictly translate to:

a) Do I keep rejected routes around?

b) Can I traffic-wise afford dropping the session to send a strong 
signal to my peer?

Hence, I didn't dig deeper.

Best regards,



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