nanog mailing list archives

Re: any dangers of filtering every /24 on full internet table to preserve FIB space ?


From: Mark Tinka <mark@tinka.africa>
Date: Tue, 11 Oct 2022 06:44:26 +0200



On 10/11/22 00:37, Matthew Petach wrote:



They became even more huffy, insisting that we were breaking the internet by not following the correct routing for the more-specific /24s which were no longer present in our tables.  No amount of trying to explain to them that they should not advertise an aggregate route if no connectivity to the more specific constituents existed seemed to get the point across.  In their eyes, advertising the /24s meant that everyone should
follow the more specific route to the final destination directly.


Certainly, an interesting, half-technical angle to consider when thinking of doing something like this.

Folk that are pushing out /24's with the expectation of the rest of the Internet steering traffic a certain way toward them, being surprised by the "brokenness" that can be created due to the decision to override "longest match" in favour of spending less cash.

Who has the right to complain the least, or the most, in such a situation?

    A: "So why don't you have a bigger router that can take our /24?"

    B: "Well, we don't have the money to afford taking a /24."

    A: "Ummh... but you are breaking BGP, and..."

    B: "Yeah... it's my Autonomous System. Sorry!"

As my South African friend would say, "It's wild".

Mark.


Current thread: