I developed an admission webhook for Akri, twice (Golang, Rust). I naively followed other examples for the generation of the certificates, created a 1.20 cluster and broke that process. I’d briefly considered using cert-manager recently but quickly abandoned the idea thinking it would be onerous and unnecessary complexity for little-old-me. I was wrong. It’s excellent and I recommend it highly. I won’t reproduce the v1beta1 and v1 examples from the Stackoverflow question as they should be self-explanatory.

I spent some time last week writing my first admission webhook for Kubernetes. I wrote the handler in Golang because I’m most familiar with Golang and because, as Kubernetes' native language, I was more confident that the necessary SDKs would exist and that the documentation would likely use Golang by default. I struggled to find useful documentation and so this post is to help you (and me!) remember how to do this next time!

I’m debugging an issue with Akri Zeroconf protocol in which Instance environment variables are no longer (!) being surfaced within the Broker pods. In my adventures, it seemed useful to better understand how Akri works and specifically, how Akri uses Kubernetes Device Plugins. IIUC plugins register with the Kubelet (!) via a gRPC service (Registration) that the Kubelet exposes on a UNIX socket at /var/lib/kubelet/device-plugins/kubelet.sock Then (!) if successful, devices should be reported by the Node’s metadata (spec) and available to be bound to Pods.