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diff --git a/man/systemd-nspawn.xml b/man/systemd-nspawn.xml
index 1f7d74e27..7d450f912 100644
--- a/man/systemd-nspawn.xml
+++ b/man/systemd-nspawn.xml
@@ -49,7 +49,17 @@
- systemd-nspawn OPTIONSCOMMANDARGS
+ systemd-nspawn
+ OPTIONS
+ COMMAND
+ ARGS
+
+
+
+ systemd-nspawn
+ -b
+ OPTIONS
+ ARGS
@@ -87,15 +97,15 @@
involved with boot and systems management.
In contrast to
- chroot1
- systemd-nspawn may be used to boot
- full Linux-based operating systems in a
- container.
+ chroot1Â systemd-nspawn
+ may be used to boot full Linux-based operating systems
+ in a container.
Use a tool like
- yum8
+ yum8,
+ debootstrap8,
or
- debootstrap8
+ pacman8
to set up an OS directory tree suitable as file system
hierarchy for systemd-nspawn
containers.
@@ -113,55 +123,96 @@
see each other. The PID namespace separation of the
two containers is complete and the containers will
share very few runtime objects except for the
- underlying file system.
+ underlying file system. It is however possible to
+ enter an existing container, see
+ Example 4 below.
+
systemd-nspawn implements the
Container
Interface specification.
+
+ As a safety check
+ systemd-nspawn will verify the
+ existence of /etc/os-release in
+ the container tree before starting the container (see
+ os-release5). It
+ might be necessary to add this file to the container
+ tree manually if the OS of the container is too old to
+ contain this file out-of-the-box.
+
+
+
+ Incompatibility with Auditing
+
+ Note that the kernel auditing subsystem is
+ currently broken when used together with
+ containers. We hence recommend turning it off entirely
+ by booting with audit=0 on the
+ kernel command line, or by turning it off at kernel
+ build time. If auditing is enabled in the kernel,
+ operating systems booted in an nspawn container might
+ refuse log-in attempts.Options
- If no arguments are passed the container is set
- up and a shell started in it, otherwise the passed
- command and arguments are executed in it. The
- following options are understood:
+ If option is specified, the
+ arguments are used as arguments for the init
+ binary. Otherwise, COMMAND
+ specifies the program to launch in the container, and
+ the remaining arguments are used as arguments for this
+ program. If is not used and no
+ arguments are specifed, a shell is launched in the
+ container.
+
+ The following options are understood:
-
+ Prints a short help
text and exits.
-
+
+
+ Prints a version string
+ and exits.
+
+
+
+ Directory to use as
file system root for the namespace
- container. If omitted the current
+ container. If omitted, the current
directory will be
used.
-
+ Automatically search
for an init binary and invoke it
instead of a shell or a user supplied
- program.
+ program. If this option is used, arguments
+ specified on the command line are used
+ as arguments for the init binary.
+
-
+ Run the command
under specified user, create home
@@ -172,10 +223,35 @@
+
+
+
+
+ Sets the machine name
+ for this container. This name may be
+ used to identify this container on the
+ host, and is used to initialize the
+ container's hostname (which the
+ container can choose to override,
+ however). If not specified, the last
+ component of the root directory of the
+ container is used.
+
+
+
+
+
+ Make the container
+ part of the specified slice, instead
+ of the
+ machine.slice.
+
+
+
- Set the specified uuid
+ Set the specified UUID
for the container. The init system
will initialize
/etc/machine-id
@@ -183,16 +259,6 @@
-
-
-
-
- Makes the container appear in
- other hierarchies that the name=systemd:/ one.
- Takes a comma-separated list of controllers.
-
-
-
@@ -207,7 +273,7 @@
Mount the root file
- system read only for the
+ system read-only for the
container.
@@ -216,12 +282,12 @@
List one or more
additional capabilities to grant the
- container. Takes a comma separated
+ container. Takes a comma-separated
list of capability names, see
capabilities7
for more information. Note that the
- the following capabilities will be
- granted in any way: CAP_CHOWN,
+ following capabilities will be granted
+ in any way: CAP_CHOWN,
CAP_DAC_OVERRIDE, CAP_DAC_READ_SEARCH,
CAP_FOWNER, CAP_FSETID, CAP_IPC_OWNER,
CAP_KILL, CAP_LEASE,
@@ -232,7 +298,9 @@
CAP_SETUID, CAP_SYS_ADMIN,
CAP_SYS_CHROOT, CAP_SYS_NICE,
CAP_SYS_PTRACE, CAP_SYS_TTY_CONFIG,
- CAP_SYS_RESOURCE, CAP_SYS_BOOT.
+ CAP_SYS_RESOURCE, CAP_SYS_BOOT,
+ CAP_AUDIT_WRITE,
+ CAP_AUDIT_CONTROL.
@@ -240,7 +308,7 @@
Control whether the
container's journal shall be made
- visible to the host system. If enabled
+ visible to the host system. If enabled,
allows viewing the container's journal
files from the host (but not vice
versa). Takes one of
@@ -248,31 +316,30 @@
host,
guest,
auto. If
- no the journal is
- not linked. If host
+ no, the journal is
+ not linked. If host,
the journal files are stored on the
- host file system (beneath the host's
- /var/log/journal)
- and a per-machine subdirectory of this
- directory is created and bind mounted
+ host file system (beneath
+ /var/log/journal/machine-id)
+ and the subdirectory is bind-mounted
into the container at the same
- location. If guest
+ location. If guest,
the journal files are stored on the
- guest file system (beneath the guest's
- /var/log/journal)
- and a per-machine subdirectory of this
- directory is symlinked into the host
+ guest file system (beneath
+ /var/log/journal/machine-id)
+ and the subdirectory is symlinked into the host
at the same location. If
- auto (the default)
- and the subdirectory of
+ auto (the default),
+ and the right subdirectory of
/var/log/journal
- exists as directory it is bind mounted
- into the container, but nothing is
- done otherwise. Effectively, booting a
- container once with
+ exists, it will be bind mounted
+ into the container. If the
+ subdirectory does not exist, no
+ linking is performed. Effectively,
+ booting a container once with
guest or
host will link the
- journal persistantly if further one
+ journal persistently if further on
the default of auto
is used.
@@ -283,6 +350,26 @@
Equivalent to
.
+
+
+
+
+
+ Bind mount a file or
+ directory from the host into the
+ container. Either takes a path
+ argument -- in which case the
+ specified path will be mounted from
+ the host to the same path in the
+ container --, or a colon-separated
+ pair of paths -- in which case the
+ first specified path is the source in
+ the host, and the second path is the
+ destination in the container. The
+ option
+ creates read-only bind
+ mount.
+
@@ -290,13 +377,13 @@
Example 1
- # yum --releasever=17 --nogpgcheck --installroot ~/fedora-tree/ install yum passwd vim-minimal rootfiles systemd
-# systemd-nspawn -D ~/fedora-tree /usr/lib/systemd/systemd
+ # yum -y --releasever=19 --nogpg --installroot=/srv/mycontainer --disablerepo='*' --enablerepo=fedora install systemd passwd yum fedora-release vim-minimal
+# systemd-nspawn -bD /srv/mycontainerThis installs a minimal Fedora distribution into
- the directory ~/fedora-tree/
- and then boots an OS in a namespace container in it,
- with systemd as init system.
+ the directory /srv/mycontainer/ and
+ then boots an OS in a namespace container in
+ it.
@@ -309,7 +396,35 @@
distribution into the directory
~/debian-tree/ and then spawns a
shell in a namespace container in it.
+
+
+
+ Example 3
+
+ # pacstrap -c -d ~/arch-tree/ base
+# systemd-nspawn -bD ~/arch-tree/
+
+ This installs a mimimal Arch Linux distribution into
+ the directory ~/arch-tree/ and then
+ boots an OS in a namespace container in it.
+
+
+
+ Example 4
+
+ To enter the container, PID of one of the
+ processes sharing the new namespaces must be used.
+ systemd-nspawn prints the PID
+ (as viewed from the outside) of the launched process,
+ and it can be used to enter the container.
+
+ # nsenter -m -u -i -n -p -t $PID
+ nsenter1
+ is part of
+ util-linux.
+ Kernel support for entering namespaces was added in
+ Linux 3.8.
@@ -324,8 +439,11 @@
systemd1,
chroot1,
+ unshare1,
yum8,
- debootstrap8
+ debootstrap8,
+ pacman8,
+ systemd.slice5