Is there a way to filter out routes that transit an AS that is a
confederation peer using an as-path access list?  I may be missing
something but I am unable to get it to work in my lab.  Say you have
the following output from sh ip bgp:

*>i191.15.0.23/32   191.15.0.2               0    100      0 (23) ?

*> 210.4.43.0       191.15.0.23              0    100      0 (23 123)
110 70 115 e

*> 210.210.20.0     191.15.0.23              0    100      0 (23 63) 70 e

*> 210.210.21.0     191.15.0.23              0    100      0 (23) 70 e

I can manipulate the AS paths external to the confederation how I want
using an as-path list applying them to the neighbor via a route-map ,
but for those AS numbers within the confederation, I am unable to
filter in this manner.  For example:
ip as-path access-list 1 deny _110_    Works
ip as-path access-list 1 deny _123_    Does not work

I have other methods for filtering this traffic as well, but I was
thinking that this would be a better solution in that I wouldn't have
to care about the specific routes from the AS in question.  Does this
make sense?  What am I missing here?

Thanks.
Cody
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