From: paguanel@gmail.com
Date: Thu Oct 09 2008 - 02:54:08 ART
Going through RFC 1771 I found nothing that said that you could not manipulate
the attributes (sent or received) of an iBGP peer.
In fact the Cisco IOS allows to modify all possible attributes of an iBGP
received/sent route: weight - inbound only- , local-preference, med,
next-hop origin and community, ( except AS PATH of course).
I find the possibility of modifying attributes other than local-as a bit at
cross purpose with the intent of maintaining consistency within an iBGP cloud.
Is this common / accepted practice of "playing" with attributes of iBGP peers ?
Here is the RFC section about consistency and common set of policies:
" If a particular AS has multiple BGP speakers and is providing transit
service for other ASs, then care must be taken to ensure a consistent
view of routing within the AS. A consistent view of the interior
routes of the AS is provided by the interior routing protocol. A
consistent view of the routes exterior to the AS can be provided by
having all BGP speakers within the AS maintain direct BGP connections
with each other.
Using a common set of policies, the BGP speakers
arrive at an agreement as to which border routers will serve as
exit/entry points for particular destinations outside the AS. This
information is communicated to the AS's internal routers, possibly
via the interior routing protocol. Care must be taken to ensure that
the interior routers have all been updated with transit information
before the BGP speakers announce to other ASs that transit service is
being provided."
http://tools.ietf.org/html/rfc1771 "
Thank you for your input
Kind Regards
Pierre-Alex
Blogs and organic groups at http://www.ccie.net
This archive was generated by hypermail 2.1.4 : Sat Nov 01 2008 - 15:35:20 ARST