nanog mailing list archives
Re: Question about AS Origin changes
From: Florian Weimer <fweimer () bfk de>
Date: Fri, 25 Mar 2011 13:53:16 +0000
* Yaoqing Liu:
I am wondering if anyone can give me possible reasons for some uncommon BGP origin change activity. What we see is that sometimes the origin for a prefix seems to change from a customer AS to it upstream provider and back. In many instances the prefix simply switches back and forth for hours or even days and sometimes very rapidly . Below I’m including an example of some of the activities I see.
This is expected if the upstream has a static route for the prefix (or a route which redistributed from another routing protocol). This could be a leftover from a non-BGP setup with the customer. Or this could be some sort of backup procedure (perhaps prompted by the instability of the BGP link). -- Florian Weimer <fweimer () bfk de> BFK edv-consulting GmbH http://www.bfk.de/ Kriegsstraße 100 tel: +49-721-96201-1 D-76133 Karlsruhe fax: +49-721-96201-99
Current thread:
- Question about AS Origin changes Yaoqing(Joey) Liu (Mar 24)
- Re: Question about AS Origin changes Florian Weimer (Mar 25)