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
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
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 2020-12-18. (At that time, the
date of the most recent commit that was found in the repository
was 2020-12-15.) 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