nanog mailing list archives
Re: 91.207.218.0/23 prefix in DFZ - AS3.21 / AS196629 - announced with AS_CONFED_SEQUENCE in AS4_PATH - propagated by 35320
From: Florian Weimer <fweimer () bfk de>
Date: Thu, 11 Dec 2008 09:34:27 +0100
* Andy Davidson:
OpenBGPd is therefore dropping the sessions when this update is received. Unideal if this attribute is learned on multiple upstreams... The impact today is fairly limited as there are relatively few bgp speakers honouring the 4-byte ASN protocol extension rules, but as code that support these features creeps around the internet, the next time this happens the impact could be much greater, so we need to understand which implementation of which BGP software caused this illegal origination.
Uhm, shouldn't you just ignore invalid AS4_PATH attributes, instead of dropping the session? It's a transient, optional attribute, so you can't rely on your peers to filter it. -- 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:
- 91.207.218.0/23 prefix in DFZ - AS3.21 / AS196629 - announced with AS_CONFED_SEQUENCE in AS4_PATH - propagated by 35320 Andy Davidson (Dec 10)
- Re: 91.207.218.0/23 prefix in DFZ - AS3.21 / AS196629 - announced with AS_CONFED_SEQUENCE in AS4_PATH - propagated by 35320 Florian Weimer (Dec 11)