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@xmission.com>
       Karel Zak <kzak@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)