NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO | AUTHORS | AVAILABILITY | COLOPHON

NSENTER(1)                      User Commands                     NSENTER(1)

NAME         top

       nsenter - run program with namespaces of other processes

SYNOPSIS         top

       nsenter [options] [program [arguments]]

DESCRIPTION         top

       Enters the namespaces of one or more other processes and then
       executes the specified program. If program is not given, then
       ``${SHELL}'' is run (default: /bin/sh).

       Enterable namespaces are:

       mount namespace
              Mounting and unmounting filesystems will not affect the rest
              of the system, except for filesystems which are explicitly
              marked as shared (with mount --make-shared; see /proc/self
              /mountinfo for the shared flag).  For further details, see
              mount_namespaces(7) and the discussion of the CLONE_NEWNS flag
              in clone(2).

       UTS namespace
              Setting hostname or domainname will not affect the rest of the
              system.  For further details, see namespaces(7) and the
              discussion of the CLONE_NEWUTS flag in clone(2).

       IPC namespace
              The process will have an independent namespace for POSIX
              message queues as well as System V message queues, semaphore
              sets and shared memory segments.  For further details, see
              namespaces(7) and the discussion of the CLONE_NEWIPC flag in
              clone(2).

       network namespace
              The process will have independent IPv4 and IPv6 stacks, IP
              routing tables, firewall rules, the /proc/net and /sys/class
              /net directory trees, sockets, etc.  For further details, see
              namespaces(7) and the discussion of the CLONE_NEWNET flag in
              clone(2).

       PID namespace
              Children will have a set of PID to process mappings separate
              from the nsenter process For further details, see
              pid_namespaces(7) and the discussion of the CLONE_NEWPID flag
              in nsenter will fork by default if changing the PID namespace,
              so that the new program and its children share the same PID
              namespace and are visible to each other.  If --no-fork is
              used, the new program will be exec'ed without forking.

       user namespace
              The process will have a distinct set of UIDs, GIDs and
              capabilities.  For further details, see user_namespaces(7) and
              the discussion of the CLONE_NEWUSER flag in clone(2).

       cgroup namespace
              The process will have a virtualized view of /proc/self/cgroup,
              and new cgroup mounts will be rooted at the namespace cgroup
              root.  For further details, see cgroup_namespaces(7) and the
              discussion of the CLONE_NEWCGROUP flag in clone(2).

       See clone(2) for the exact semantics of the flags.

OPTIONS         top

       Various of the options below that relate to namespaces take an
       optional file argument.  This should be one of the /proc/[pid]/ns/*
       files described in namespaces(7).

       -a, --all
              Enter all namespaces of the target process by the default
              /proc/[pid]/ns/* namespace paths. The default paths to the
              target process namespaces may be overwritten by namespace
              specific options (e.g. --all --mount=[path]).

              The user namespace will be ignored if the same as the caller's
              current user namespace. It prevents a caller that has dropped
              capabilities from regaining those capabilities via a call to
              setns().  See setns(2) for more details.

       -t, --target pid
              Specify a target process to get contexts from.  The paths to
              the contexts specified by pid are:

              /proc/pid/ns/mnt    the mount namespace
              /proc/pid/ns/uts    the UTS namespace
              /proc/pid/ns/ipc    the IPC namespace
              /proc/pid/ns/net    the network namespace
              /proc/pid/ns/pid    the PID namespace
              /proc/pid/ns/user   the user namespace
              /proc/pid/ns/cgroup the cgroup namespace
              /proc/pid/root      the root directory
              /proc/pid/cwd       the working directory respectively

       -m, --mount[=file]
              Enter the mount namespace.  If no file is specified, enter the
              mount namespace of the target process.  If file is specified,
              enter the mount namespace specified by file.

       -u, --uts[=file]
              Enter the UTS namespace.  If no file is specified, enter the
              UTS namespace of the target process.  If file is specified,
              enter the UTS namespace specified by file.

       -i, --ipc[=file]
              Enter the IPC namespace.  If no file is specified, enter the
              IPC namespace of the target process.  If file is specified,
              enter the IPC namespace specified by file.

       -n, --net[=file]
              Enter the network namespace.  If no file is specified, enter
              the network namespace of the target process.  If file is
              specified, enter the network namespace specified by file.

       -p, --pid[=file]
              Enter the PID namespace.  If no file is specified, enter the
              PID namespace of the target process.  If file is specified,
              enter the PID namespace specified by file.

       -U, --user[=file]
              Enter the user namespace.  If no file is specified, enter the
              user namespace of the target process.  If file is specified,
              enter the user namespace specified by file.  See also the
              --setuid and --setgid options.

       -C, --cgroup[=file]
              Enter the cgroup namespace.  If no file is specified, enter
              the cgroup namespace of the target process.  If file is
              specified, enter the cgroup namespace specified by file.

       -G, --setgid gid
              Set the group ID which will be used in the entered namespace
              and drop supplementary groups.  nsenter(1) always sets GID for
              user namespaces, the default is 0.

       -S, --setuid uid
              Set the user ID which will be used in the entered namespace.
              nsenter(1) always sets UID for user namespaces, the default is
              0.

       --preserve-credentials
              Don't modify UID and GID when enter user namespace. The
              default is to drops supplementary groups and sets GID and UID
              to 0.

       -r, --root[=directory]
              Set the root directory.  If no directory is specified, set the
              root directory to the root directory of the target process.
              If directory is specified, set the root directory to the
              specified directory.

       -w, --wd[=directory]
              Set the working directory.  If no directory is specified, set
              the working directory to the working directory of the target
              process.  If directory is specified, set the working directory
              to the specified directory.

       -F, --no-fork
              Do not fork before exec'ing the specified program.  By
              default, when entering a PID namespace, nsenter calls fork
              before calling exec so that any children will also be in the
              newly entered PID namespace.

       -Z, --follow-context
              Set the SELinux security context used for executing a new
              process according to already running process specified by
              --target PID. (The util-linux has to be compiled with SELinux
              support otherwise the option is unavailable.)

       -V, --version
              Display version information and exit.

       -h, --help
              Display help text and exit.

SEE ALSO         top

       clone(2), setns(2), namespaces(7)

AUTHORS         top

       Eric Biederman ⟨biederm@xmission.com⟩
       Karel Zak ⟨kzak@redhat.com⟩

AVAILABILITY         top

       The nsenter command is part of the util-linux package and is
       available from Linux Kernel Archive 
       ⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩.

COLOPHON         top

       This page is part of the util-linux (a random collection of Linux
       utilities) project.  Information about the project can be found at 
       ⟨https://www.kernel.org/pub/linux/utils/util-linux/⟩.  If you have a
       bug report for this manual page, send it to
       util-linux@vger.kernel.org.  This page was obtained from the
       project's upstream Git repository
       ⟨git://git.kernel.org/pub/scm/utils/util-linux/util-linux.git⟩ on
       2017-11-25.  (At that time, the date of the most recent commit that
       was found in the repository was 2017-11-23.)  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
       man-pages@man7.org

util-linux                        June 2013                       NSENTER(1)

Pages that refer to this page: nsenter(1)unshare(1)setns(2)namespaces(7)lsns(8)