website/content/en/docs/reference/glossary/userns.md

title	id	date	full_link	short_description	aka	tags
user namespace	userns	2021-07-13	https://man7.org/linux/man-pages/man7/user_namespaces.7.html	A Linux kernel feature to emulate superuser privilege for unprivileged users.		security

A kernel feature to emulate root. Used for "rootless containers".

User namespaces are a Linux kernel feature that allows a non-root user to emulate superuser ("root") privileges, for example in order to run containers without being a superuser outside the container.

User namespace is effective for mitigating damage of potential container break-out attacks.

In the context of user namespaces, the namespace is a Linux kernel feature, and not a {{< glossary_tooltip text="namespace" term_id="namespace" >}} in the Kubernetes sense of the term.