nanog mailing list archives
Re: Lots of prepends - AS20912 case
From: Jon Lewis <jlewis () lewis org>
Date: Fri, 20 Feb 2009 08:00:46 -0500 (EST)
On Fri, 20 Feb 2009, Giuliano Peritore wrote:
The problem is that differently to Cisco the syntax of the prepend field on thius system is not a string (eg. "20912 20912 20912") but an integer, that the user interface _should_ limit to the interval 0-16.
...
The producer has been warned about the problem, which I can't completely define as a "bug"... but the lack of a user configuration helper (syntax checker).
More important than whether or not to consider this a bug, it seems a very shortsighted way to support prepending. If your prepend "field" is an integer controlling how many times to prepend, how do you control which ASN(s) or even AS Paths are prepended? It sounds like you probably can't. As has been discussed recently, there are cases where you might want to prepend a creative AS Path for traffic engineering purposes to force certain routes/paths to be ignored by certain ASNs.
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Current thread:
- Lots of prepends - AS20912 case Giuliano Peritore (Feb 20)
- Re: Lots of prepends - AS20912 case Tomas Caslavsky (Feb 20)
- Re: Lots of prepends - AS20912 case Jon Lewis (Feb 20)
- Re: Lots of prepends - AS20912 case Dorn Hetzel (Feb 20)
- Re: Lots of prepends - AS20912 case Mikael Abrahamsson (Feb 20)
- Re: Lots of prepends - AS20912 case Mathias Sundman (Feb 20)
- Re: Lots of prepends - AS20912 case Dorn Hetzel (Feb 20)
- RE: Lots of prepends - AS20912 case Ivan Pepelnjak (Feb 20)
- Re: Lots of prepends - AS20912 case Dorn Hetzel (Feb 20)
- Re: Lots of prepends - AS20912 case Dorn Hetzel (Feb 20)