I am having a BGP path attribute problem I was hoping to get some clarity on.
The main problem is Ibgp routes being preferred over the ebgp route always unless I tweak the path attributes.
As seen in the picture I have three routers. R3 is running Ibgp with R1 and R3 is running ebgp with R2. I advertised the same loop back address from both R1 and R3. Regardless of which was learned first, Ibgp is always preferred. Both are advertised with the network command.
I can correct this with locally setting the weight on R3 for routes received from R2 but I’m curious as to why R3 prefers the path advertised by R1 when everything is default/the same and ibgp AD is 200 and ebgp AD is 20.
Unless I’m mistaken AD is used between routing protocols and with bgp the path attributes are considered first then Administrative distance.
Thus if everything is left the same ebgp should win out?
Any insight would be greatly appreciated!