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NSENTER(1)                       User Commands                      NSENTER(1)

NAME
       nsenter - run program with namespaces of other processes
SYNOPSIS
       nsenter [options] [program [arguments]]
DESCRIPTION
       Enters  the namespaces of one or more other processes and then executes
       the specified program.  Enterable namespaces are:
       mount namespace
              Mounting and unmounting filesystems will not affect the rest  of
              the  system (CLONE_NEWNS flag), except for filesystems which are
              explicitly marked as shared (with mount --make-shared; see /proc
              /self/mountinfo for the shared flag).
       UTS namespace
              Setting  hostname  or domainname will not affect the rest of the
              system.  (CLONE_NEWUTS flag)
       IPC namespace
              The process will have an independent namespace for System V mes-
              sage queues, semaphore sets and shared memory segments.  (CLONE_
              NEWIPC flag)
       network namespace
              The process will have independent IPv4 and IPv6 stacks, IP rout-
              ing  tables,  firewall  rules,  the /proc/net and /sys/class/net
              directory trees, sockets, etc.  (CLONE_NEWNET flag)
       PID namespace
              Children will have a set of PID  to  process  mappings  separate
              from the nsenter process (CLONE_NEWPID flag).  nsenter will fork
              by default if changing the PID namespace, so that the  new  pro-
              gram and its children share the same PID namespace and are visi-
              ble 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 capabili-
              ties.  (CLONE_NEWUSER flag)
       See clone(2) for the exact semantics of the flags.
       If program is not given, then ``${SHELL}'' is run (default: /bin/sh).

OPTIONS
       -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/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.
       -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 --tar-
              get 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
       setns(2), clone(2)
AUTHORS
       Eric Biederman <biederm AT xmission.com>
       Karel Zak <kzak AT redhat.com>
AVAILABILITY
       The  nsenter command is part of the util-linux package and is available
       from Linux Kernel  Archive  <ftp://ftp.kernel.org/pub/linux/utils/util-
       linux/>.

util-linux                         June 2013                        NSENTER(1)