This will be the BGP Topology you will very likely be working Trouble tickets from on the TSHOOT, it could be iBGP or eBGP, and there is a whole lot of BGP to know even for that! Review of BGP BGP is called a "Path Vector" Protocol that basically is the internet at Layer 3, … Continue reading TSHOOT – Gigantic BGP review, verification commands, and troubleshooting for exam day!
Same Topology, only this time I added a second logical network between R3 and R4 by creating 2 loopback interfaces in the same subnet 126.96.36.199 /24, and removed the previous "All or none" configuration for Local Preference. So first I want to review R2 and R1 to see if their ip bgp tables look correct: … Continue reading Local Preference Part 2: Configuring the “Some but not all” local preference attribute, behaviors, and explanations!
We are back with this Topology I believe once more before we switch gears and leave Path and Attribute discussion alone for a bit. One quick real world note, I fired up my lab and I was missing R4's loopback network / Peering across all routers, and I started troubleshooting when I stopped and saw … Continue reading BGP Best-Path selection process examined given its criteria for selection, IMPORTANT behaviors of iBGP vs eBGP, Next-Hop examined in detail, and more!
^ I created this mid-session, but put it here as well as I like to illustrate the struggle at the beginning of the post 🙂 There are 3 well-known and mandatory attributes a BGP Speaker includes in updates to other BGP Speakers, that they must know how to speak (or they aren't speaking BGP) which … Continue reading BGP Well-Known Mandatory attributes explained, Best-Path explained, configured, and VERY important details!