[derefr]

K8s is a “datacenter operating system”, just like VMWare’s own VSphere, or Mesos, Mosix, etc. These solutions also compete for mindshare with mainframe solutions like IBM’s; and with “control planes” like OpenStack, Canonical’s Landscape, or (I think?) Microsoft’s System Center. This space is very, very profitable.

None of this applies to Docker itself. Docker is “just” a virtualization technology. Sure, Docker Swarm exists, but at this point it’s mostly used as a shimming UI for connecting the Docker client and daemon to the abstractions mentioned above, not a clustering solution in its own right. Swarm lost in the DCOS market. And the market for pure virtualization solutions isn’t anywhere near the market for DCOSes.

[Blackstone4]

Doesn't K8s typically run on virtual machines? In which case it's K8s + VMs to get to the “datacenter operating system” model?

[gtaylor]

It can run on VMs but doesn't have to. There are many bare metal k8s users out there doing some really neat things with the stack.