lxc-unshare can be used to run a task in a cloned set of namespaces.
This command is mainly provided for testing purposes. Despite its
name, it always uses clone rather than unshare to create the new task
with fresh namespaces. Apart from testing kernel regressions this
should make no difference.
-s, --namespaces namespaces
Specify the namespaces to attach to, as a pipe-separated list,
e.g. NETWORK|IPC. Allowed values are MOUNT, PID, UTSNAME, IPC,
USER and NETWORK. This allows one to change the context of
the process to e.g. the network namespace of the container
while retaining the other namespaces as those of the host.
(The pipe symbol needs to be escaped, e.g. MOUNT\|PID or
quoted, e.g. "MOUNT|PID".)
-u, --user user
Specify a userid which the new task should become.
-H, --hostname hostname
Set the hostname in the new container. Only allowed if the
UTSNAME namespace is set.
-i, --ifname interfacename
Move the named interface into the container. Only allowed if
the NETWORK namespace is set. You may specify this argument
multiple times to move multiple interfaces into container.
Daemonize (do not wait for the container to exit before
Mount default filesystems (/proc /dev/shm and /dev/mqueue) in
the container. Only allowed if MOUNT namespace is set.
To spawn a new shell with its own UTS (hostname) namespace,
lxc-unshare -s UTSNAME /bin/bash
If the hostname is changed in that shell, the change will not be
reflected on the host.
To spawn a shell in a new network, pid, and mount namespace,
lxc-unshare -s "NETWORK|PID|MOUNT" /bin/bash
The resulting shell will have pid 1 and will see no network
interfaces. After re-mounting /proc in that shell,
mount -t proc proc /proc
ps output will show there are no other processes in the namespace.
To spawn a shell in a new network, pid, mount, and hostname
lxc-unshare -s "NETWORK|PID|MOUNT|UTSNAME" -M -H myhostname -i veth1 /bin/bash
The resulting shell will have pid 1 and will see two network
interfaces (lo and veth1). The hostname will be "myhostname" and
/proc will have been remounted. ps output will show there are no
other processes in the namespace.
This page is part of the lxc (Linux containers) project. Information
about the project can be found at ⟨http://linuxcontainers.org/⟩. If
you have a bug report for this manual page, send it to
firstname.lastname@example.org. This page was obtained from the
project's upstream Git repository ⟨git://github.com/lxc/lxc⟩ on
2020-07-14. (At that time, the date of the most recent commit that
was found in the repository was 2020-07-08.) If you discover any
rendering problems in this HTML version of the page, or you believe
there is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to