Small MPLS Test Network Built With OpenBSD
A few months ago, I wrote a diff to simplify the calculation of ICMP extension header checksums in the OpenBSD kernel. It so happened that the code is only used by the OpenBSD MPLS subsystem. I didn’t have access to an OpenBSD-based MPLS network at the time, nor was I familiar with MPLS in general; so in the spirit of the OpenBSD hacker mantra “shut up and hack,” I set out to build a small MPLS test network to test my diff.
You don't need to be a genius to debug a pf.conf firewall ruleset, you just need the guts to run tcpdump