BGP route selection

[Arvin Gan]

Hi,
I notice that there is a description of route selection algorithm:

  The global best route selection algorithm is (roughly) as follows:

  *   Preferences of the routes are compared.
  *   Source protocol instance preferences are compared.
  *   If source protocols are the same (e.g. BGP vs. BGP), the protocol's route selection algorithm is invoked.
  *   If source protocols are different (e.g. BGP vs. OSPF), result of the algorithm is undefined.
  And I also notice that normally the  configuration  "Administrative Distance"  that is mapped to preference under channel  in bird  is different between eBGP (default  value 20) and iBGP (default value 200).

My question is : If iBgp preference is lower than eBGP preference that mean iBGP priority higher than eBGP,   iBGP route is selected or eBGP route is selected, do anyone know it? But in BGP instance, eGBP is prior than iBGP....   Appreciated in advance!

Thanks
Arvin
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