[c-nsp] BGP path preference

[Jon Lewis]

On Fri, 31 Aug 2007, Oliver Boehmer (oboehmer) wrote:

>>> On Wed, 29 Aug 2007, Andy Dills wrote:
>>>> Don't forget that you can prepend incoming announcements as well as
>>>> outgoing announcements.
>>>
>>> This is what I'd do (and have done before) to even things out.  Some
>>> would argue that when prepending received routes in a route-map, you
>>> should prepend with your own ASN.
>>
>> Once you pass that route to an iBGP speaker, it'll drop it as it sees
>> its own ASN in the path
>
> well, IOS only performs the loop check when receiving paths from
> external neighbors. But you would set the as-path prepend on your
> outbound external sessions, little need of doing this within your AS,
> usually..

Not necessarily, and not in the case the original poster was trying to 
solve (prepending received routes to even things up between "tier 1" and 
not quite "tier 1" transits and balance outgoing traffic).

----------------------------------------------------------------------
  Jon Lewis                   |  I route
  Senior Network Engineer     |  therefore you are
  Atlantic Net                |
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