Are there any containers running without namespaces and cgroups?

Question

Most container runtimes are based on namespaces and cgroups (docker, lxc, runc). I am wondering if there are on-the-market or open-source containers that are not based on these technologies? Do you know some names?

Answer 1

Before the introduction of cgroups and namespaces, the isolation consisted to use chroot() . But this was insufficient from a security point of view. As only the file system was isolated. And it is possible to escape from a "chrooted" environment.

This link provides an history of the containerization techniques in the Unix/Linux world.