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  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.

OPTIONS

       -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.

       -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 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 namespace.

                 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.

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)

AUTHOR

       Daniel Lezcano <daniel.lezcano@free.fr>

                                            2024-01-24                             lxc-unshare(1)