CKA/CKAD exam: Managing ETCD cluster

A bit of context.

As part of preparation for my Certified Kubernetes Administrator (CKA) and Certified Kubernetes Application Developer (CKAD) exams, I had to take deep dive into managing Etcd cluster routines and grind through all manual processes of installing, adding, removing nodes, managing certificates, so on and so forth. Etcd is not something that is new to me, I worked with Etcd clusters before and used it during a few projects, but havent had a chance to work with Etcd in very recent past. In other words, didn't touch it for a few years. To my surprise and awe, Etcd has evolved into quite an advanced and mature product. Hence, this little story on how to manage Etcd cluster and a few road-bumps I stumbled upon, and, of course, all in context of preparing for the exams.

Let’s do some Etcd-ing

As all of you know, Etcd is a critical component for Kubernetes as it stores the entire state of the cluster: its configuration, specifications, and the statuses of the running workloads. You may think of it as a memory of Kubernetes. Here’s quick link to Etc Operations guide, to which I will refer a lot in following sections. Also, the link to the classic Kubernetes The Hard Way, although Kelsey’s guideline uses a few GCP CLI commands and GCP environment, mine is deployed in AWS environment so you’ll see a…