lxc-unshare(1) — Linux manual page
lxc-unshare(1) lxc-unshare(1)
NAME
lxc-unshare - Run a task in a new set of namespaces.
SYNOPSIS
lxc-unshare {-s, --namespaces namespaces} [-u, --user user] [-H,
--hostname hostname] [-i, --ifname ifname] [-d,
--daemon] [-M, --remount] {command}
DESCRIPTION
lxc-unshare can be used to run a task in a cloned set of name‐
spaces. 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.
OPTIONS
-s, --namespaces namespaces
Specify the namespaces to attach to, as a pipe-separated
list, e.g. NETWORK|IPC. Allowed values are MOUNT, PID, UT‐
SNAME, 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 ar‐
gument multiple times to move multiple interfaces into
container.
-d, --daemon
Daemonize (do not wait for the container to exit before
exiting)
-M, --remount
Mount default filesystems (/proc /dev/shm and /dev/mqueue)
in the container. Only allowed if MOUNT namespace is set.
EXAMPLES
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 in‐
terfaces. After re-mounting /proc in that shell,
mount -t proc proc /proc
ps output will show there are no other processes in the name‐
space.
To spawn a shell in a new network, pid, mount, and hostname name‐
space.
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 in‐
terfaces (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.
SEE ALSO
lxc(7), lxc-create(1), lxc-copy(1), lxc-destroy(1), lxc-start(1),
lxc-stop(1), lxc-execute(1), lxc-console(1), lxc-monitor(1),
lxc-wait(1), lxc-cgroup(1), lxc-ls(1), lxc-info(1),
lxc-freeze(1), lxc-unfreeze(1), lxc-attach(1), lxc.conf(5)
COLOPHON
This page is part of the lxc (Linux containers) project. Infor‐
mation about the project can be found at
⟨http://linuxcontainers.org/⟩. If you have a bug report for this
manual page, send it to lxc-devel@lists.linuxcontainers.org.
This page was obtained from the project's upstream Git repository
⟨https://github.com/lxc/lxc.git⟩ on 2024-06-14. (At that time,
the date of the most recent commit that was found in the
repository was 2024-06-05.) If you discover any rendering
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