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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal" style="text-indent:9.75pt">I notice that there is a description of route selection algorithm:<o:p></o:p></p>
<p style="background:#F2FCFE"> <span style="font-size:9.5pt;font-family:"Arial",sans-serif;color:black">
The global best route selection algorithm is (roughly) as follows:<o:p></o:p></span></p>
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<li class="MsoNormal" style="color:black;mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1;background:#F2FCFE">
<span style="font-size:9.5pt;font-family:"Arial",sans-serif">Preferences of the routes are compared.<o:p></o:p></span></li><li class="MsoNormal" style="color:black;mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1;background:#F2FCFE">
<span style="font-size:9.5pt;font-family:"Arial",sans-serif">Source protocol instance preferences are compared.<o:p></o:p></span></li><li class="MsoNormal" style="color:black;mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1;background:#F2FCFE">
<span style="font-size:9.5pt;font-family:"Arial",sans-serif">If source protocols are the same (e.g. BGP vs. BGP), the protocol's route selection algorithm is invoked.<o:p></o:p></span></li><li class="MsoNormal" style="color:black;mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1;background:#F2FCFE">
<span style="font-size:9.5pt;font-family:"Arial",sans-serif">If source protocols are different (e.g. BGP vs. OSPF), result of the algorithm is undefined.<o:p></o:p></span></li></ul>
<p class="MsoNormal"> 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).
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">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!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks<o:p></o:p></p>
<p class="MsoNormal">Arvin<o:p></o:p></p>
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