> -Original Message-
> From: NANOG On
> Behalf Of Joe Maimon
> Sent: Thursday, March 31, 2022 6:20 PM
> Subject: Re: DMARC ViolationAS21299 - 46.42.196.0/24 ASN prepending 255
> times
>
> [...]
> I think more and perhaps different knobs were and still are needed
Matthew Petach wrote:
Unfortunately, the reason crazy-long prepends actually propagate so
widely in the internet core is because most of those decisions to prefer
your peer's customers are done using a relatively big and heavy hammer.
IOW if your peer or customer has prepended 5 times or
On Thu, Mar 31, 2022 at 3:16 PM Joe Maimon wrote:
>
>
> Joe Provo wrote:
> > On Fri, Mar 25, 2022 at 11:08:01AM +0300, Paschal Masha wrote:
> >> :) probably the longest prepend in the world.
> >>
> >> A thought though, is it breaking any standard or best practice
> procedures?
> >
> > That said,
Joe Provo wrote:
On Fri, Mar 25, 2022 at 11:08:01AM +0300, Paschal Masha wrote:
:) probably the longest prepend in the world.
A thought though, is it breaking any standard or best practice procedures?
That said, prepending pretty much anything more than your current view
of the Internet's
og
Subject: Re: DMARC ViolationAS21299 - 46.42.196.0/24 ASN prepending 255 times
Mostly what Matt said. ( I should have also said 'ride the 0/0 train INTO the
DFZ, my mistake.)
Essentially, if ASN X is announcing a prefix with an excessive number of
prepends, they are saying to the world '
On Sun, 27 Mar 2022 at 18:31, Jon Lewis wrote:
> Is prepending used for any purpose other than TE? The point I think Joe
> was trying to make was prepending once or even a few times has uses.
> Prepending more than a few times is unlikely to accomplish anything a few
> prepends didn't get done.
On Fri, 25 Mar 2022, Baldur Norddahl wrote:
On Fri, 25 Mar 2022 at 17:32, Joe Provo wrote:
That said, prepending pretty much anything more than your current view
of the Internet's diameter in ASNs is useless in practice.
That is one way of viewing it. But prepending can also be us
ompson*
> Consultant, Infrastructure Services
> [image: MERLIN]
> 100 - 135 Innovation Drive
> Winnipeg, MB, R3T 6A8
> (204) 977-6824 or 1-800-430-6404 (MB only)
> athomp...@merlin.mb.ca
> www.merlin.mb.ca
>
>
>
> *From:* NANOG *On Behalf
> Of *Tom Beecher
> *Se
On Fri, Mar 25, 2022 at 6:19 PM Amir Herzberg wrote:
> Hi Matthew and NANOG,
>
> I don't want to defend prepending 255 times, and can understand filtering
> of extra-prepended-announcements, but I think Matthew may not be correct
> here:
>
>> Anyone that is prepending to do traffic engineering is
Hi Matthew and NANOG,
I don't want to defend prepending 255 times, and can understand filtering
of extra-prepended-announcements, but I think Matthew may not be correct
here:
> Anyone that is prepending to do traffic engineering is
> doing *differential* prepending; that is, a longer number
> of
On Fri, Mar 25, 2022 at 2:59 PM Adam Thompson
wrote:
> Tom, how exactly does someone “ride the 0/0” train in the DFZ?
>
It's not so much "ride the 0/0 train" as much as it is
"treat excessive prepends as network-unreachable"
Think of prepends beyond say 10 prepends as a way
to signal "infinite"
> (204) 977-6824 or 1-800-430-6404 (MB only)
> athomp...@merlin.mb.ca
> www.merlin.mb.ca
>
> From: NANOG On Behalf Of Tom
> Beecher
> Sent: Friday, March 25, 2022 4:13 PM
> To: Paschal Masha
> Cc: nanog
> Subject: Re: DMARC ViolationAS21299 - 46.42.196.0/24 ASN prepending
omp...@merlin.mb.ca>
www.merlin.mb.ca<http://www.merlin.mb.ca/>
From: NANOG On Behalf Of Tom
Beecher
Sent: Friday, March 25, 2022 4:13 PM
To: Paschal Masha
Cc: nanog
Subject: Re: DMARC ViolationAS21299 - 46.42.196.0/24 ASN prepending 255 times
The best practice with regards to as_path lengt
The best practice with regards to as_path length is to have an edge filter
that dumps any prefix with a length longer than say 10. Depending on the
situation, might even be able to go smaller.
At a certain point, keeping that route around does nothing for you, just
shoot it and ride the 0/0 train.
On Fri, 25 Mar 2022 at 17:32, Joe Provo wrote:
> That said, prepending pretty much anything more than your current view
> of the Internet's diameter in ASNs is useless in practice.
>
That is one way of viewing it. But prepending can also be used for traffic
engineering. I could prepend 1 to my f
On Fri, Mar 25, 2022 at 11:08:01AM +0300, Paschal Masha wrote:
> :) probably the longest prepend in the world.
>
> A thought though, is it breaking any standard or best practice procedures?
Many popular BGP implementations have historically had weaknesses
with excessively long AS-paths. Best pra
Paschal Masha writes:
> :) probably the longest prepend in the world.
>
> A thought though, is it breaking any standard or best practice procedures?
Don't think so. But there is this draft suggesting max 5:
https://datatracker.ietf.org/doc/draft-ietf-grow-as-path-prepending/
Bjørn
:) probably the longest prepend in the world.
A thought though, is it breaking any standard or best practice procedures?
Regards
Paschal Masha | Engineering
Skype ID: paschal.masha
- Original Message -
From: "Erik Sundberg"
To: "nanog"
Sent: Friday, March 25, 2022 6:43:38 AM
Subject:
18 matches
Mail list logo