nanog mailing list archives
Re: Lots of prepends - AS20912 case
From: Tomas Caslavsky <tomas () caslavsky cz>
Date: Fri, 20 Feb 2009 12:29:25 +0100
Hi all,I can only cofnirm that AS47868 is using also Mikrotik as their border BGP router
Tomas Giuliano Peritore wrote:
The long (176) AS20912 prepend incident was due to a misconfiguration of a BGP router we were testing.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.Unfortunately something has gone wrong with the syntax checker so you can enter a number (the number entered, thinking to Cisco syntax, was 20912) and the sotware interpreted it as the request of 20912 prepends... (0x51B0), dropped the highest 8 bits and processed it as the request of 0xB0=176 prepends.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).I think that the case of AS47868 is the same, because I seed the modulo was involved too.Many thanks to one of our upstream providers for their support. --------------------------------------------------- Giuliano Peritore - g.peritore () panservice it Direzione Generale - Panservice Servizi professionali per Internet ed il Networking Panservice e' associata AIIP -- RIPE Local Registry Phone: +39 0773 410020 Fax +39 0773 470219 Numero verde: 800 901492 - http://www.panservice.it ---------------------------------------------------
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)