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 message
queues, semaphore sets and shared memory segments. (CLONE_NEWIPC
flag)
- 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. (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 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.
(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 user namespace.
- -S, --setuid uid
- Set the user ID which will be used in the entered user namespace.
- -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.
- -V, --version
- Display version information and exit.
- -h, --help
- Display help text and exit.
SEE ALSO¶
setns(2),
clone(2)
AUTHOR¶
Eric Biederman
AVAILABILITY¶
The nsenter command is part of the util-linux package and is available from
Linux
Kernel Archive