Solaris&#x2F;Illumos&#x2F;SmartOS (Joyent&#x27;s O&#x2F;S, Joyent being Cantrill&#x27;s company that offers a public cloud like AWS), has built-in lightweight containers that have all the right isolation characteristics (esp. security)<p>Docker&#x2F;CoreOS build upon Linux primitives for isolated name spaces, but security is a problem because of Linux&#x27;s flawed implementation. But Docker is the flavor of the month, even though it is technically inferior to SmartOS&#x27;s.<p>So they (Joyent, Cantrill&#x27;s company) wrapped SmartOS with the docker remote API, so when you do &#x27;docker ps&#x27;, you see all the  VMs in the entire data center. The whole cloud works as one machine.