Setting sensible max-prefix limits

Hank Nussbacher hank at
Wed Aug 18 11:53:26 UTC 2021

On 18/08/2021 13:03, Chriztoffer Hansen wrote:
> On Wed, 18 Aug 2021 at 11:33, Lars Prehn <lprehn at> wrote:
>> I guess for long standing peers one could just eyeball it, e.g., current
>> prefix count + some safety margin. How does that work for new peers?
> If you have automation in place. Another approach is to count the
> received prefix. Store the counted value in a database. Based on the
> avg prefix count over X (time period). Add e.g. 10 - 25 % headroom
> over the avg prefix count and use the calculated value as the
> max-prefix limit?

That works but all too often people forget to update it.  Set a 
quarterly reminder in your calendar to check max-prefix setting.


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