- <varname>pidns</varname>,
- <varname>openvz</varname> to test
- against a specific implementation. The
- test may be negated by prepending an
- exclamation mark.
+ <varname>bochs</varname>,
+ <varname>chroot</varname>,
+ <varname>openvz</varname>,
+ <varname>lxc</varname>,
+ <varname>lxc-libvirt</varname>,
+ <varname>systemd-nspawn</varname>,
+ <varname>pidns</varname> to test
+ against a specific implementation. If
+ multiple virtualization technologies
+ are nested only the innermost is
+ considered. The test may be negated by
+ prepending an exclamation mark.