Quick notes in Docker in relation to LXC.

Docker is a front end single application virtualization engine based on OS level virtualization LXC (Linux Containers), but what is exciting here,

• Portable - single file (I believe)
• Low overhead - should run inside of my Ubuntu KVM
• Has become cross-platform (in a sense) 
• Works with the vanilla Linux kernel (no patching).

Unlike LXC containers Docker containers do not behave like lightweight VMs and cannot be treated as such. Docker containers are restricted to a single application by design. The Docker base OS template is pared down to a single app environment and does not have a proper init or support things like services, daemons, syslog, cron or running multiple applications. (from http://www.flockport.com/lxc-vs-docker/ - this can be explained and worded better?). In addition Docker containers are ephemeral as your only option. Unlike LCX which is an option, "lxc-start-ephemeral".

See my hosting page for Virtualization technologies.

However, after a bit more reading this all seems very limiting, but I this is by design. If forces both Ops and Developers into a repeatable automated approach to building servers and coding applications. This fundamentally shifts how we manage servers and application containers.... now we think in terms of orchestration of operating systems, containers and code as one singular unit.

In fact, it seems that Docker has great marketing that overshadows LXC. In order to compete, Ubuntu has built out LXD which is a simpler front-end to LXC.

I've taken a look at LXD,

• It has the same core team from LXC is behind
• At the core this is all still LXC
• Provides API for higher level orchestration of Containers

Bottom line, LXC is what I've been doing in Solaris Containers but for Linux.

References

LXC vs Docker - http://www.flockport.com/lxc-vs-docker/

Discusses security - https://blog.docker.com/2013/08/containers-docker-how-secure-are-they/