Hello Thejohn,
- neighbor neighbor-id additional-paths send: We use this to configure the router so it sends multiple BGP paths to a neighbor.
- neighbor neighbor-id additional-paths receive: If you have a neighbor that sends multiple paths, that’s nice but you still have to configure your local router that it wants to receive multiple paths.
- bgp additional-paths select : you receive a bunch of paths from your neighbor but you can still configure your router which of these paths you actually want to use.
- bgp additional-paths install: this tells the router to actually install a backup path that you selected with the “bgp additional-paths install” command.
- neighbor neighbor-id advertise additional-paths: This configures your router which additional-paths you want to advertise to a neighbor. “all” means all additional-paths.
These options make more sense if you see them in action. Try to recreate the topology I did in my lesson. When you try each command, look at the BGP and CEF table to see what is actually advertised/received/installed on each device. That makes it much easier to understand all of this.
Hope this helps!
Rene