The old version was using a slightly confusing way to
show which pods were receiving traffic:
kubectl logs --tail 1 --selector app=rng
(And then we look at the timestamp of the last request.)
In this new version, concepts are introduced progressively;
the YAML parser magic is isolated from the other concerns;
we show the impact of removing a pod from load balancing
in a way that is (IMHO) more straightforward:
- follow logs of specific pod
- remove pod from load balancer
- logs instantly stop flowing
These slides also explain why the DaemonSet and the
ReplicaSet for the rng service don't step on each other's
toes.
kubectl run is being deprecated as a multi-purpose tool.
This PR replaces 'kubectl run' with 'kubectl create deployment'
in most places (except in the very first example, to reduce the
cognitive load; and when we really want a single-shot container).
It also updates the places where we use a 'run' label, since
'kubectl create deployment' uses the 'app' label instead.
NOTE: this hasn't gone through end-to-end testing yet.
This was discussed and agreed in #246. It will probably break a few
outstanding PRs as well as a few external links but it's for the
better good long term.
