[johannes1234321]

Back in the nineties I stumbled over the dot, when a friend of mine claimed his mail address was `[e-mail].` insisting on the dot. I proved him wrong, claiming it didn't matter. Only a few years later, when dealing with DNS config I learned the truth... now it's knowledge I can use to be alone in a bar.

But more recently that knowledge got some relevance in Kubernetes clusters to me: By default they use the `cluster.local.` domain. As that is configurable, now many people leave that out and rely on the search domain config. In consequence in some situations a broken service may try to connect to the outside and with bad choice of i.e. namespace names might leak as valid host names on the public DNS ... which in worst names can lead to a connection attempt from cluster to some foreign system.