Documentation

debugindex

Name

bgp router debug dp -  examine the BGP decision process steps

Synopsis

dp <prefix> 

Arguments

prefix
destination prefix to examine

Description

This command allows to examine the decision process steps in one router for a specifix prefix. The command takes a single argument, the destination prefix. The command shows the current best route. Then it lists the feasible routes available towards the specified destination. Finally, it shows each rule of the decision process and which routes remain after it.

Here is an example of the output generated by this command. Four routes are available. All the routes have the same LOCAL-PREF, the same AS-PATH length, the same ORIGIN and the same MED value. All the routes are learned by 198.32.12.9 through iBGP. The tie-break occurs with the rule based on the IGP cost to the next-hop. After this rule, only one route remains and the decision process stops. cbgp> bgp router 198.32.12.9 debug dp 204.222.228/24
Debug Decision Process
----------------------
AS11537, 198.32.12.9, 204.222.228.0/24

[ Current Best route: ]
*> 204.222.228.0/24 138.18.47.33 100 0 668 5978 i

[ Eligible routes: ]
* 204.222.228.0/24 138.18.155.13 100 0 668 5978 i
* 204.222.228.0/24 198.32.153.25 100 0 668 5978 i
* 204.222.228.0/24 198.32.170.37 100 0 668 5978 i
*> 204.222.228.0/24 138.18.47.33 100 0 668 5978 i

[ Highest LOCAL-PREF ]
[ Shortest AS-PATH ]
[ Lowest ORIGIN ]
[ Lowest MED ]
[ eBGP over iBGP ]
[ Nearest NEXT-HOP ]
*> 204.222.228.0/24 138.18.47.33 100 0 668 5978 i

[ Best route ]
*> 204.222.228.0/24 138.18.47.33 100 0 668 5978 i