Analyzing AS PATH in packets

[Julien Sansonnens]

Dear all,

using bird 2.0.7

I'm a bit confused with the output of "show route export". I'm exporting a
full table to a downstream. I'm expecting to see my own AS as the first AS
in AS PATH but it will not show in "BGP.as_path"
If I prepend it, then it appears on the output.

I don't know if it's related to display, or if my AS is really not added to
the PATH. Perhaps it is added later in the process, before leaving my
router ?

How can I check this? I tried with "debug", but to my knowledge, it is not
possible to display route details. I thought about doing tcpdump, but I
haven't found out how to interpret the result correctly and see the AS
PATH.
Would you have a clue on how to see exactly what is being exported on an
interface?

 thanks a lot
Julien
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