Nerd blog.

14 Oct 2022

exabgp 4.x, anycast, and healthchecks

This is a fifth in a blog series about DNS, specifically to address changes in exabgp 4.x, and how its built in healthcheck works.
01 Sep 2020

nginx ISP fence

restricting an nginx application to one or more ISPs
14 Apr 2020

OpenBSD 6.6 BGP Looking Glass

OpenBSD 6.6 BGP Looking Glass
01 Feb 2020

MPLS Labels Explained

Sometimes the easiest way to understand a complex subject is just to see it in action.
29 Jan 2020

Troubleshooting a Duplicate OSPF Router ID

I ran into an strange issue today. The problem was reported as "can't upload on a speed test".