Teaching Kubernetes
The first thing I do when I look at kubernetes tutorials is look at ingress or load-balancing... and usually I find it absent.It is not the fault of the author (and I commend them for taking the trouble), but Kubernetes is super complex for getting traffic inside the cluster. But here's a genuine appeal from someone who has suffered this before.In kubernetes, you have multiple types of ingresses - and you invariably need to have a combination of them to get anything done correctly. For example nginx-ingress will lose source-ip info and will not do L4 proxying very well. Which is why the unsaid point of all kubernetes deployments is "use ELB or GLB with proxy protocol and call it a day".I get why - K8s is trying to solve the most complex problems first and trickling it down. Which means for the time being, ingress is a very hard problem to solve in k8s.The second place where every one will get stuck is calico vs weave vs flannel vs whatever. Most tutorials say "use any one of them and let's move on". Unfortunately, that is not the case - choose your network plugins wisely.After spending a lot of time in k8s, I setup a Docker Swarm cluster in about 3 hours. It does not have some of the more complex usecases supported but it does three things super well - networking, ingress and secrets ... and for most beginners, that's all they need.P.S. i have the exact same stack running on kubernetes and docker swarmDocker Compose yml form 3.1 is brilliant - other than my docker files, i need a 30 line yml file to deploy my whole stack across 3 machines. Kubernetes on the other hand  needs atleast 12 yml files ("deployments" and "services"). I'm not counting another 4 yml files for statefulsets and persistentvolumeclaim since there is nothing equivalent in docker swarm