Question about BGP FAQ on cisco.com

From: Hobbs (deadheadblues@gmail.com)
Date: Wed Dec 03 2008 - 22:10:03 ARST


Hello,

Please reference:
http://www.ciscosystems.com/en/US/tech/tk365/technologies_q_and_a_item09186a00800949e8.shtml#

As far as I can tell the order of operations for route filtering are (This
is the 3rd question on the FAQ):

For inbound updates the order of preference is:
   1. route-map
   2. filter-list
   3. prefix-list, distribute-list

For outbound updates the order of preference is:
   1. prefix-list, distribute-list
   2. filter-list
   3. route-map

However, further down is this question and answer (5th from the bottom):

Q. How can I filter all IP routes advertised to a BGP neighbor except the
default route 0.0.0.0/0?
    A. The specific routes can be filtered if you use inbound filter-list,
distribute-list, prefix-list and route-map all at the same time for the same
bgp neighbor. This is the order of operation:
       1. Filter-list
       2. Router-map
       3. Distribute-list (or) prefix-list

Is this last question conflicting the previous one?
What's the difference between only allowing a default route as opposed to
only allowing certain other routes?

thank you

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