Hello,
This is a pretty "beginner" level question, I am just struggling to understand the full picture and am hoping someone can explain things in simpler terms. My goal is to attempt to replicate ThousandEyes's BGP monitoring, SPECIFICALLY it's "Path Changes" alerts.
1. I don't fully understand what this is using to alert. I understand SW can alert on Routing Neighbor changes, but what I don't fully understand is how that relates to TE and its "Path Changes". My best understanding is that the "Routing Neighbor" is the primary next hop router in the routing table, and that alerting on a Neighbor change would be akin to alerting on a "Path Change", assuming I have this alert set up for every device along a specific path.
2. If this is correct, I am still wondering how this would be used to alert on a path change that is outside of my organization. In my head it seems reasonable to assume that I could have a trace route, and alert if one of the hops on the route is not the primary hop that would be expected, and alert on that. This would allow for me to know if traffic is going an unexpected way at any point in the journey, however I cannot figure out how something like that would be done.
Forgive me, I am very green to both SW and Networking, and am more than happy to read up if anyone can point me to what I need. I spent about 8 hours yesterday trying to understand this and cannot. I can see the path in NPM and it's frustrating that this functionality seems just within my reach.
