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Comment by bc569a80a344f9c | Hacker News Reader

Buy some routers that have BGP implementations (there are some cheap ones, Mikrotik for example), or use open source implementations. The article lists bird, another very popular one is FRR (free range routing). You can trivially stand up two docker containers, stand up a BGP session between them, and - for example - propagate static routes you set up within them.

If you like guided tutorials, https://blog.ipspace.net/2023/08/bgp-labs-basic-setup/ is rather good and has been extended to somewhat advanced topics. Everything needed to follow along is free software.

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A good tool to try this stuff is containerlab: https://containerlab.dev/

It lets you setup multiple containers with direct connections between them in whatever topology you want. It allows you to run both Linux containers (with FRR for example) and emulated versions of popular router platforms (some of the ones mentioned in the article).

OpenBSD include bgpd(8) out of the box:

  DESCRIPTION
     bgpd is a Border Gateway Protocol (BGP) daemon which manages the network
     routing tables.  Its main purpose is to exchange information concerning
     "network reachability" with other BGP systems.  bgpd uses the Border
     Gateway Protocol, Version 4, as described in RFC 4271.

And a looking glass interface ready to go

At least to me one of the challenges is relating to the problems that BGP solves. You can get pretty far in network complexity before BGP (or OSPF etc) really does anything for you. What would be good scenarios one could encounter in "homelab" situation where BGP would be beneficial?

There are no scenarios where BGP contained within your home lab is beneficial for anything other than learning BGP. It's the routing protocol for the Internet. Its whole point is scaling globally, and - crucially - enabling making routing decisions that aren't just based on path weights. OSPF, IS-IS, EIGRP, whatever, they are all just path finding algorithms; OSPF is quite literally Dijkstra. That's great when you want to find the shortest or fastest path to somewhere, but that's not how the Internet works: it's quite reasonable for an operator to want to take the cheapest path (in terms of money), or to take the path that avoids specific foreign countries. BGP is expressive enough to write routing policy like that. You don't need that in your homelab, unless you want to learn BGP, either because you need to for work or to further your career, or because you're curious about it.

Running a few Kubernetes nodes with a network plane like Cilium that supports using BGP to inform your router about which container IP is on which node is a simple-ish one.

Not really, unless you have thousands of routes to manage across large numbers of gateways. Otherwise, running BGP inside your homelab is just a learning tool.

*crickets*

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