Docker is an opinionated way to use containers. You don't need to adopt that to get the benefits of containers. A lot of the messaging, hype and marketing confl

Docker is an opinionated way to use containers. You don't need to adopt that to get the benefits of containers. A lot of the messaging, hype and marketing conflates the 2 and it suits the docker ecosystem to do that but it does not benefit informed discussion. By eschewing plain containers in favour of Docker you are embracing some complexity and it would help to have more discussions on the tradeoff and benefits of every approach, rather than just conflating containers to Docker. The LXC project in development since 2009 on which Docker was based and now Systemd-nspawn give you pretty advanced containers with mature management tools, multiple container OSs, full stack linux networking, storage options, cloning, snapshotting etc. [1] LXC and soon Systemd-nspawn (version 220) support unprivileged containers [2] that let's non root users run containers. That's a pretty big step forward for container security. There is lot of innovation happening outside the hype of Docker. But these projects are not opinionated and stop at giving you container technology as lightweight VMs like KVM, Xen, Vmware stop at giving you virtualization. Docker takes that as a base and restricts the container OS template to a single app, builds the container as layers using aufs, btrfs, device mapper, and enforces storage separation. This is not rocket science, you can do this yourself with overlayfs, aufs, btrfs, build single app containers etc [3] By adopting the Docker way you are immediately taking away seamless migration of VM workloads and embracing some complexity. There are both upsides and downsides to this. For a lot of use cases the Docker approach may help, in others it may add unnecessary complexity. We have an indepth [4] look at the differences between LXC and Docker here for those who are interested. Disclosure I run flockport.com that provides an app store for servers based on Linux containers. [1] https://flockport.com/guides https://flockport.com/guides [2] https://www.flockport.com/lxc-using-unprivileged-containers/ https://www.flockport.com/lxc-using-unprivileged-containers/ [3] https://www.flockport.com/experimenting-with-overlayfs https://www.flockport.com/experimenting-with-overlayfs [4] https://www.flockport.com/lxc-vs-docker https://www.flockport.com/lxc-vs-docker