To be honest, I have not tried to manipulate the AS_PATH on iBGP session which is exactly what you are trying to do here. Could this be the culprit? Please recall that under normal circumstances, the AS_PATH is modified only between eBGP neighbors. Is it possible that the other BGP routers you have are modifying the AS_PATH on eBGP sessions?
I user prepending on IBGP all the time but most of my gear is not Cisco. I did also try setting to the ebgp peer it also has with no change. Its like its just ignoring the route-map. I have this same setup on some cisco routers with no issue. Just the 3560 switch. Any idea's?
I have just tested this on 2691 series 12.4(15)T13 Advanced IP Services IOSes, and I can confirm that in iBGP peerings, the AS_PATH modification in the outbound route-map does not apply, i.e. it is ignored just as you have experienced here. As soon as the peering is changed to eBGP, the AS_PATH modification works as specified in the route-map.
I am confused as to what configuration on Cisco devices actually worked for you - based on my experiments, iBGP peerings can not be forced to arbitrarily modify the AS_PATH attribute.
I actually have several ibgp peers that Im injecting the prepend but they are not Cisco routers. I have a few older cisco routers that work fine with this setup. This is interesting, I will have to use localpref to change the routing path for those devices. I appreciate your looking into this.
You are welcome. I can see how this behavior may have changed between old and new IOS versions. In any case, I can see the logic with the current behavior - that in iBGP peerings, AS_PATH is not modified. I believe this is a grey area in BGP specification that is open to interpretation, and various vendors may implement this behavior differently.
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.