All things Linux containers

A container a day keeps the pager away!

terminology | namespaces | cgroups | filesytems | tooling | see also

This little website here is dedicated to the documentation of Linux containers. As mentioned elsewhere, in a sense there are no containers per se, but Linux kernel features such as namespaces and cgroups that are bundled and used in different ways to provide an abstraction we call container. Examples of this bundling are Docker, CoreOS appc, OCI runc, Canonical LXC/LXD, and OpenVZ.


Conceptually, a Linux container is made up of three things:

A container's core is a process (group). The ER diagram for namespaces, cgroups and process (groups) looks as follows:

namespaces, cgroups and process (groups) ER diagram

Read above ER diagram as: a process (group) can be in one or more namespaces and can be controlled by one or more cgroups

Linux namespaces


Linux cgroups


COW filesystems


namespaces and cgroups

See also …

namespaces and cgroups