man/systemd-nspawn.xml

   1 <?xml version='1.0'?> <!--*-nxml-*-->
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   3         "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
   4
   5 <!--
   6   This file is part of systemd.
   7
   8   Copyright 2010 Lennart Poettering
   9
  10   systemd is free software; you can redistribute it and/or modify it
  11   under the terms of the GNU Lesser General Public License as published by
  12   the Free Software Foundation; either version 2.1 of the License, or
  13   (at your option) any later version.
  14
  15   systemd is distributed in the hope that it will be useful, but
  16   WITHOUT ANY WARRANTY; without even the implied warranty of
  17   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18   Lesser General Public License for more details.
  19
  20   You should have received a copy of the GNU Lesser General Public License
  21   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  22 -->
  23
  24 <refentry id="systemd-nspawn"
  25           xmlns:xi="http://www.w3.org/2001/XInclude">
  26
  27         <refentryinfo>
  28                 <title>systemd-nspawn</title>
  29                 <productname>systemd</productname>
  30
  31                 <authorgroup>
  32                         <author>
  33                                 <contrib>Developer</contrib>
  34                                 <firstname>Lennart</firstname>
  35                                 <surname>Poettering</surname>
  36                                 <email>lennart@poettering.net</email>
  37                         </author>
  38                 </authorgroup>
  39         </refentryinfo>
  40
  41         <refmeta>
  42                 <refentrytitle>systemd-nspawn</refentrytitle>
  43                 <manvolnum>1</manvolnum>
  44         </refmeta>
  45
  46         <refnamediv>
  47                 <refname>systemd-nspawn</refname>
  48                 <refpurpose>Spawn a namespace container for debugging, testing and building</refpurpose>
  49         </refnamediv>
  50
  51         <refsynopsisdiv>
  52                 <cmdsynopsis>
  53                         <command>systemd-nspawn</command>
  54                         <arg choice="opt" rep="repeat">OPTIONS</arg>
  55                         <arg choice="opt"><replaceable>COMMAND</replaceable>
  56                         <arg choice="opt" rep="repeat">ARGS</arg>
  57                         </arg>
  58                 </cmdsynopsis>
  59                 <cmdsynopsis>
  60                         <command>systemd-nspawn</command>
  61                         <arg choice="plain">-b</arg>
  62                         <arg choice="opt" rep="repeat">OPTIONS</arg>
  63                         <arg choice="opt" rep="repeat">ARGS</arg>
  64                 </cmdsynopsis>
  65         </refsynopsisdiv>
  66
  67         <refsect1>
  68                 <title>Description</title>
  69
  70                 <para><command>systemd-nspawn</command> may be used to
  71                 run a command or OS in a light-weight namespace
  72                 container. In many ways it is similar to
  73                 <citerefentry><refentrytitle>chroot</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
  74                 but more powerful since it fully virtualizes the file
  75                 system hierarchy, as well as the process tree, the
  76                 various IPC subsystems and the host and domain
  77                 name.</para>
  78
  79                 <para><command>systemd-nspawn</command> limits access
  80                 to various kernel interfaces in the container to
  81                 read-only, such as <filename>/sys</filename>,
  82                 <filename>/proc/sys</filename> or
  83                 <filename>/sys/fs/selinux</filename>. Network
  84                 interfaces and the system clock may not be changed
  85                 from within the container. Device nodes may not be
  86                 created. The host system cannot be rebooted and kernel
  87                 modules may not be loaded from within the
  88                 container.</para>
  89
  90                 <para>Note that even though these security precautions
  91                 are taken <command>systemd-nspawn</command> is not
  92                 suitable for secure container setups. Many of the
  93                 security features may be circumvented and are hence
  94                 primarily useful to avoid accidental changes to the
  95                 host system from the container. The intended use of
  96                 this program is debugging and testing as well as
  97                 building of packages, distributions and software
  98                 involved with boot and systems management.</para>
  99
 100                 <para>In contrast to
 101                 <citerefentry><refentrytitle>chroot</refentrytitle><manvolnum>1</manvolnum></citerefentry> <command>systemd-nspawn</command>
 102                 may be used to boot full Linux-based operating systems
 103                 in a container.</para>
 104
 105                 <para>Use a tool like
 106                 <citerefentry><refentrytitle>yum</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 107                 <citerefentry><refentrytitle>debootstrap</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 108                 or
 109                 <citerefentry><refentrytitle>pacman</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 110                 to set up an OS directory tree suitable as file system
 111                 hierarchy for <command>systemd-nspawn</command>
 112                 containers.</para>
 113
 114                 <para>Note that <command>systemd-nspawn</command> will
 115                 mount file systems private to the container to
 116                 <filename>/dev</filename>,
 117                 <filename>/run</filename> and similar. These will
 118                 not be visible outside of the container, and their
 119                 contents will be lost when the container exits.</para>
 120
 121                 <para>Note that running two
 122                 <command>systemd-nspawn</command> containers from the
 123                 same directory tree will not make processes in them
 124                 see each other. The PID namespace separation of the
 125                 two containers is complete and the containers will
 126                 share very few runtime objects except for the
 127                 underlying file system. Use
 128                 <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
 129                 <command>login</command> command to request an
 130                 additional login prompt in a running container.</para>
 131
 132                 <para><command>systemd-nspawn</command> implements the
 133                 <ulink
 134                 url="http://www.freedesktop.org/wiki/Software/systemd/ContainerInterface">Container
 135                 Interface</ulink> specification.</para>
 136
 137                 <para>As a safety check
 138                 <command>systemd-nspawn</command> will verify the
 139                 existence of <filename>/etc/os-release</filename> in
 140                 the container tree before starting the container (see
 141                 <citerefentry><refentrytitle>os-release</refentrytitle><manvolnum>5</manvolnum></citerefentry>). It
 142                 might be necessary to add this file to the container
 143                 tree manually if the OS of the container is too old to
 144                 contain this file out-of-the-box.</para>
 145         </refsect1>
 146
 147         <refsect1>
 148                 <title>Options</title>
 149
 150                 <para>If option <option>-b</option> is specified, the
 151                 arguments are used as arguments for the init
 152                 binary. Otherwise, <replaceable>COMMAND</replaceable>
 153                 specifies the program to launch in the container, and
 154                 the remaining arguments are used as arguments for this
 155                 program. If <option>-b</option> is not used and no
 156                 arguments are specifed, a shell is launched in the
 157                 container.</para>
 158
 159                 <para>The following options are understood:</para>
 160
 161                 <variablelist>
 162                         <varlistentry>
 163                                 <term><option>-D</option></term>
 164                                 <term><option>--directory=</option></term>
 165
 166                                 <listitem><para>Directory to use as
 167                                 file system root for the container. If
 168                                 neither <option>--directory=</option>
 169                                 nor <option>--image=</option> are
 170                                 specified, the current directory will
 171                                 be used. May not be specified together with
 172                                 <option>--image=</option>.</para></listitem>
 173                         </varlistentry>
 174
 175                         <varlistentry>
 176                                 <term><option>-i</option></term>
 177                                 <term><option>--image=</option></term>
 178
 179                                 <listitem><para>Disk image to mount
 180                                 the root directory for the container
 181                                 from. Takes a path to a regular file
 182                                 or to a block device node. The file or
 183                                 block device must contain a GUID
 184                                 Partition Table with a root partition
 185                                 which is mounted as the root directory
 186                                 of the container. Optionally, it may
 187                                 contain a home and/or a server data
 188                                 partition which are mounted to the
 189                                 appropriate places in the
 190                                 container. All these partitions must
 191                                 be identified by the partition types
 192                                 defined by the <ulink
 193                                 url="http://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/">Discoverable
 194                                 Partitions Specification</ulink>. Any
 195                                 other partitions, such as foreign
 196                                 partitions, swap partitions or EFI
 197                                 system partitions are not mounted. May
 198                                 not be specified together with
 199                                 <option>--directory=</option>.</para></listitem>
 200                         </varlistentry>
 201
 202                         <varlistentry>
 203                                 <term><option>-b</option></term>
 204                                 <term><option>--boot</option></term>
 205
 206                                 <listitem><para>Automatically search
 207                                 for an init binary and invoke it
 208                                 instead of a shell or a user supplied
 209                                 program. If this option is used,
 210                                 arguments specified on the command
 211                                 line are used as arguments for the
 212                                 init binary. This option may not be
 213                                 combined with
 214                                 <option>--share-system</option>.
 215                                 </para></listitem>
 216                         </varlistentry>
 217
 218                         <varlistentry>
 219                                 <term><option>-u</option></term>
 220                                 <term><option>--user=</option></term>
 221
 222                                 <listitem><para>After transitioning
 223                                 into the container, change to the
 224                                 specified user-defined in the
 225                                 container's user database. Like all
 226                                 other systemd-nspawn features, this is
 227                                 not a security feature and provides
 228                                 protection against accidental
 229                                 destructive operations
 230                                 only.</para></listitem>
 231                         </varlistentry>
 232
 233                         <varlistentry>
 234                                 <term><option>-M</option></term>
 235                                 <term><option>--machine=</option></term>
 236
 237                                 <listitem><para>Sets the machine name
 238                                 for this container. This name may be
 239                                 used to identify this container on the
 240                                 host, and is used to initialize the
 241                                 container's hostname (which the
 242                                 container can choose to override,
 243                                 however). If not specified, the last
 244                                 component of the root directory of the
 245                                 container is used.</para></listitem>
 246                         </varlistentry>
 247
 248                         <varlistentry>
 249                                 <term><option>--uuid=</option></term>
 250
 251                                 <listitem><para>Set the specified UUID
 252                                 for the container. The init system
 253                                 will initialize
 254                                 <filename>/etc/machine-id</filename>
 255                                 from this if this file is not set yet.
 256                                 </para></listitem>
 257                         </varlistentry>
 258
 259                         <varlistentry>
 260                                 <term><option>--slice=</option></term>
 261
 262                                 <listitem><para>Make the container
 263                                 part of the specified slice, instead
 264                                 of the default
 265                                 <filename>machine.slice</filename>.</para>
 266                                 </listitem>
 267                         </varlistentry>
 268
 269                         <varlistentry>
 270                                 <term><option>--private-network</option></term>
 271
 272                                 <listitem><para>Disconnect networking
 273                                 of the container from the host. This
 274                                 makes all network interfaces
 275                                 unavailable in the container, with the
 276                                 exception of the loopback device and
 277                                 those specified with
 278                                 <option>--network-interface=</option>
 279                                 and configured with
 280                                 <option>--network-veth</option>. If
 281                                 this option is specified, the
 282                                 CAP_NET_ADMIN capability will be added
 283                                 to the set of capabilities the
 284                                 container retains. The latter may be
 285                                 disabled by using
 286                                 <option>--drop-capability=</option>.</para></listitem>
 287                         </varlistentry>
 288
 289                         <varlistentry>
 290                                 <term><option>--network-interface=</option></term>
 291
 292                                 <listitem><para>Assign the specified
 293                                 network interface to the
 294                                 container. This will remove the
 295                                 specified interface from the calling
 296                                 namespace and place it in the
 297                                 container. When the container
 298                                 terminates, it is moved back to the
 299                                 host namespace. Note that
 300                                 <option>--network-interface=</option>
 301                                 implies
 302                                 <option>--private-network</option>. This
 303                                 option may be used more than once to
 304                                 add multiple network interfaces to the
 305                                 container.</para></listitem>
 306                         </varlistentry>
 307
 308                         <varlistentry>
 309                                 <term><option>--network-macvlan=</option></term>
 310
 311                                 <listitem><para>Create a
 312                                 <literal>macvlan</literal> interface
 313                                 of the specified Ethernet network
 314                                 interface and add it to the
 315                                 container. A
 316                                 <literal>macvlan</literal> interface
 317                                 is a virtual interface that adds a
 318                                 second MAC address to an existing
 319                                 physical Ethernet link. The interface
 320                                 in the container will be named after
 321                                 the interface on the host, prefixed
 322                                 with <literal>mv-</literal>. Note that
 323                                 <option>--network-macvlan=</option>
 324                                 implies
 325                                 <option>--private-network</option>. This
 326                                 option may be used more than once to
 327                                 add multiple network interfaces to the
 328                                 container.</para></listitem>
 329                         </varlistentry>
 330
 331                         <varlistentry>
 332                                 <term><option>--network-veth</option></term>
 333
 334                                 <listitem><para>Create a virtual
 335                                 Ethernet link
 336                                 (<literal>veth</literal>) between host
 337                                 and container. The host side of the
 338                                 Ethernet link will be available as a
 339                                 network interface named after the
 340                                 container's name (as specified with
 341                                 <option>--machine=</option>), prefixed
 342                                 with <literal>ve-</literal>. The
 343                                 container side of the Ethernet
 344                                 link will be named
 345                                 <literal>host0</literal>. Note that
 346                                 <option>--network-veth</option>
 347                                 implies
 348                                 <option>--private-network</option>.</para></listitem>
 349                         </varlistentry>
 350
 351                         <varlistentry>
 352                                 <term><option>--network-bridge=</option></term>
 353
 354                                 <listitem><para>Adds the host side of
 355                                 the Ethernet link created with
 356                                 <option>--network-veth</option> to the
 357                                 specified bridge. Note that
 358                                 <option>--network-bridge=</option>
 359                                 implies
 360                                 <option>--network-veth</option>. If
 361                                 this option is used, the host side of
 362                                 the Ethernet link will use the
 363                                 <literal>vb-</literal> prefix instead
 364                                 of <literal>ve-</literal>.</para></listitem>
 365                         </varlistentry>
 366
 367                         <varlistentry>
 368                                 <term><option>-Z</option></term>
 369                                 <term><option>--selinux-context=</option></term>
 370
 371                                 <listitem><para>Sets the SELinux
 372                                 security context to be used to label
 373                                 processes in the container.</para>
 374                                 </listitem>
 375                         </varlistentry>
 376
 377                         <varlistentry>
 378                                 <term><option>-L</option></term>
 379                                 <term><option>--selinux-apifs-context=</option></term>
 380
 381                                 <listitem><para>Sets the SELinux security
 382                                 context to be used to label files in
 383                                 the virtual API file systems in the
 384                                 container.</para>
 385                                 </listitem>
 386                         </varlistentry>
 387
 388                         <varlistentry>
 389                                 <term><option>--capability=</option></term>
 390
 391                                 <listitem><para>List one or more
 392                                 additional capabilities to grant the
 393                                 container. Takes a comma-separated
 394                                 list of capability names, see
 395                                 <citerefentry><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 396                                 for more information. Note that the
 397                                 following capabilities will be granted
 398                                 in any way: CAP_CHOWN,
 399                                 CAP_DAC_OVERRIDE, CAP_DAC_READ_SEARCH,
 400                                 CAP_FOWNER, CAP_FSETID, CAP_IPC_OWNER,
 401                                 CAP_KILL, CAP_LEASE,
 402                                 CAP_LINUX_IMMUTABLE,
 403                                 CAP_NET_BIND_SERVICE,
 404                                 CAP_NET_BROADCAST, CAP_NET_RAW,
 405                                 CAP_SETGID, CAP_SETFCAP, CAP_SETPCAP,
 406                                 CAP_SETUID, CAP_SYS_ADMIN,
 407                                 CAP_SYS_CHROOT, CAP_SYS_NICE,
 408                                 CAP_SYS_PTRACE, CAP_SYS_TTY_CONFIG,
 409                                 CAP_SYS_RESOURCE, CAP_SYS_BOOT,
 410                                 CAP_AUDIT_WRITE,
 411                                 CAP_AUDIT_CONTROL. Also CAP_NET_ADMIN
 412                                 is retained if
 413                                 <option>--private-network</option> is
 414                                 specified. If the special value
 415                                 <literal>all</literal> is passed, all
 416                                 capabilities are
 417                                 retained.</para></listitem>
 418                         </varlistentry>
 419
 420                         <varlistentry>
 421                                 <term><option>--drop-capability=</option></term>
 422
 423                                 <listitem><para>Specify one or more
 424                                 additional capabilities to drop for
 425                                 the container. This allows running the
 426                                 container with fewer capabilities than
 427                                 the default (see above).</para></listitem>
 428                         </varlistentry>
 429
 430                         <varlistentry>
 431                                 <term><option>--link-journal=</option></term>
 432
 433                                 <listitem><para>Control whether the
 434                                 container's journal shall be made
 435                                 visible to the host system. If enabled,
 436                                 allows viewing the container's journal
 437                                 files from the host (but not vice
 438                                 versa). Takes one of
 439                                 <literal>no</literal>,
 440                                 <literal>host</literal>,
 441                                 <literal>guest</literal>,
 442                                 <literal>auto</literal>. If
 443                                 <literal>no</literal>, the journal is
 444                                 not linked. If <literal>host</literal>,
 445                                 the journal files are stored on the
 446                                 host file system (beneath
 447                                 <filename>/var/log/journal/<replaceable>machine-id</replaceable></filename>)
 448                                 and the subdirectory is bind-mounted
 449                                 into the container at the same
 450                                 location. If <literal>guest</literal>,
 451                                 the journal files are stored on the
 452                                 guest file system (beneath
 453                                 <filename>/var/log/journal/<replaceable>machine-id</replaceable></filename>)
 454                                 and the subdirectory is symlinked into the host
 455                                 at the same location. If
 456                                 <literal>auto</literal> (the default),
 457                                 and the right subdirectory of
 458                                 <filename>/var/log/journal</filename>
 459                                 exists, it will be bind mounted
 460                                 into the container. If the
 461                                 subdirectory does not exist, no
 462                                 linking is performed. Effectively,
 463                                 booting a container once with
 464                                 <literal>guest</literal> or
 465                                 <literal>host</literal> will link the
 466                                 journal persistently if further on
 467                                 the default of <literal>auto</literal>
 468                                 is used.</para></listitem>
 469                         </varlistentry>
 470
 471                         <varlistentry>
 472                                 <term><option>-j</option></term>
 473
 474                                 <listitem><para>Equivalent to
 475                                 <option>--link-journal=guest</option>.</para></listitem>
 476                         </varlistentry>
 477
 478                         <varlistentry>
 479                                 <term><option>--read-only</option></term>
 480
 481                                 <listitem><para>Mount the root file
 482                                 system read-only for the
 483                                 container.</para></listitem>
 484                         </varlistentry>
 485
 486                         <varlistentry>
 487                                 <term><option>--bind=</option></term>
 488                                 <term><option>--bind-ro=</option></term>
 489
 490                                 <listitem><para>Bind mount a file or
 491                                 directory from the host into the
 492                                 container. Either takes a path
 493                                 argument -- in which case the
 494                                 specified path will be mounted from
 495                                 the host to the same path in the
 496                                 container --, or a colon-separated
 497                                 pair of paths -- in which case the
 498                                 first specified path is the source in
 499                                 the host, and the second path is the
 500                                 destination in the container. The
 501                                 <option>--bind-ro=</option> option
 502                                 creates read-only bind
 503                                 mounts.</para></listitem>
 504                         </varlistentry>
 505
 506                         <varlistentry>
 507                                 <term><option>--setenv=</option></term>
 508
 509                                 <listitem><para>Specifies an
 510                                 environment variable assignment to
 511                                 pass to the init process in the
 512                                 container, in the format
 513                                 <literal>NAME=VALUE</literal>. This
 514                                 may be used to override the default
 515                                 variables or to set additional
 516                                 variables. This parameter may be used
 517                                 more than once.</para></listitem>
 518                         </varlistentry>
 519
 520                         <varlistentry>
 521                                 <term><option>--share-system</option></term>
 522
 523                                 <listitem><para>Allows the container
 524                                 to share certain system facilities
 525                                 with the host. More specifically, this
 526                                 turns off PID namespacing, UTS
 527                                 namespacing and IPC namespacing, and
 528                                 thus allows the guest to see and
 529                                 interact more easily with processes
 530                                 outside of the container. Note that
 531                                 using this option makes it impossible
 532                                 to start up a full Operating System in
 533                                 the container, as an init system
 534                                 cannot operate in this mode. It is
 535                                 only useful to run specific programs
 536                                 or applications this way, without
 537                                 involving an init system in the
 538                                 container. This option implies
 539                                 <option>--register=no</option>. This
 540                                 option may not be combined with
 541                                 <option>--boot</option>.</para></listitem>
 542                         </varlistentry>
 543
 544                         <varlistentry>
 545                                 <term><option>--register=</option></term>
 546
 547                                 <listitem><para>Controls whether the
 548                                 container is registered with
 549                                 <citerefentry><refentrytitle>systemd-machined</refentrytitle><manvolnum>8</manvolnum></citerefentry>. Takes
 550                                 a boolean argument, defaults to
 551                                 <literal>yes</literal>. This option
 552                                 should be enabled when the container
 553                                 runs a full Operating System (more
 554                                 specifically: an init system), and is
 555                                 useful to ensure that the container is
 556                                 accessible via
 557                                 <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 558                                 and shown by tools such as
 559                                 <citerefentry><refentrytitle>ps</refentrytitle><manvolnum>1</manvolnum></citerefentry>. If
 560                                 the container does not run an init
 561                                 system, it is recommended to set this
 562                                 option to <literal>no</literal>. Note
 563                                 that <option>--share-system</option>
 564                                 implies
 565                                 <option>--register=no</option>.
 566                                 </para></listitem>
 567                         </varlistentry>
 568
 569                         <varlistentry>
 570                                 <term><option>--keep-unit</option></term>
 571
 572                                 <listitem><para>Instead of creating a
 573                                 transient scope unit to run the
 574                                 container in, simply register the
 575                                 service or scope unit
 576                                 <command>systemd-nspawn</command> has
 577                                 been invoked in with
 578                                 <citerefentry><refentrytitle>systemd-machined</refentrytitle><manvolnum>8</manvolnum></citerefentry>. This
 579                                 has no effect if
 580                                 <option>--register=no</option> is
 581                                 used. This switch should be used if
 582                                 <command>systemd-nspawn</command> is
 583                                 invoked from within a service unit,
 584                                 and the service unit's sole purpose
 585                                 is to run a single
 586                                 <command>systemd-nspawn</command>
 587                                 container. This option is not
 588                                 available if run from a user
 589                                 session.</para></listitem>
 590                         </varlistentry>
 591
 592                         <varlistentry>
 593                                 <term><option>--personality=</option></term>
 594
 595                                 <listitem><para>Control the
 596                                 architecture ("personality") reported
 597                                 by
 598                                 <citerefentry><refentrytitle>uname</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 599                                 in the container. Currently, only
 600                                 <literal>x86</literal> and
 601                                 <literal>x86-64</literal> are
 602                                 supported. This is useful when running
 603                                 a 32-bit container on a 64-bit
 604                                 host. If this setting is not used,
 605                                 the personality reported in the
 606                                 container is the same as the one
 607                                 reported on the
 608                                 host.</para></listitem>
 609                         </varlistentry>
 610
 611                         <varlistentry>
 612                                 <term><option>-q</option></term>
 613                                 <term><option>--quiet</option></term>
 614
 615                                 <listitem><para>Turns off any status
 616                                 output by the tool itself. When this
 617                                 switch is used, the only output
 618                                 from nspawn will be the console output
 619                                 of the container OS itself.</para></listitem>
 620                         </varlistentry>
 621
 622                         <xi:include href="standard-options.xml" xpointer="help" />
 623                         <xi:include href="standard-options.xml" xpointer="version" />
 624                 </variablelist>
 625
 626         </refsect1>
 627
 628         <refsect1>
 629                 <title>Example 1</title>
 630
 631                 <programlisting># yum -y --releasever=19 --nogpg --installroot=/srv/mycontainer --disablerepo='*' --enablerepo=fedora install systemd passwd yum fedora-release vim-minimal
 632 # systemd-nspawn -bD /srv/mycontainer</programlisting>
 633
 634                 <para>This installs a minimal Fedora distribution into
 635                 the directory <filename noindex='true'>/srv/mycontainer/</filename> and
 636                 then boots an OS in a namespace container in
 637                 it.</para>
 638         </refsect1>
 639
 640         <refsect1>
 641                 <title>Example 2</title>
 642
 643                 <programlisting># debootstrap --arch=amd64 unstable ~/debian-tree/
 644 # systemd-nspawn -D ~/debian-tree/</programlisting>
 645
 646                 <para>This installs a minimal Debian unstable
 647                 distribution into the directory
 648                 <filename>~/debian-tree/</filename> and then spawns a
 649                 shell in a namespace container in it.</para>
 650         </refsect1>
 651
 652         <refsect1>
 653                 <title>Example 3</title>
 654
 655                 <programlisting># pacstrap -c -d ~/arch-tree/ base
 656 # systemd-nspawn -bD ~/arch-tree/</programlisting>
 657
 658                 <para>This installs a mimimal Arch Linux distribution into
 659                 the directory <filename>~/arch-tree/</filename> and then
 660                 boots an OS in a namespace container in it.</para>
 661         </refsect1>
 662
 663         <refsect1>
 664                 <title>Example 4</title>
 665
 666                 <programlisting># mv ~/arch-tree /var/lib/container/arch
 667 # systemctl enable systemd-nspawn@arch.service
 668 # systemctl start systemd-nspawn@arch.service</programlisting>
 669
 670                 <para>This makes the Arch Linux container part of the
 671                 <filename>multi-user.target</filename> on the host.
 672                 </para>
 673         </refsect1>
 674
 675         <refsect1>
 676                 <title>Example 5</title>
 677
 678                 <programlisting># btrfs subvolume snapshot / /.tmp
 679 # systemd-nspawn --private-network -D /.tmp -b</programlisting>
 680
 681                 <para>This runs a copy of the host system in a
 682                 btrfs snapshot.</para>
 683         </refsect1>
 684
 685         <refsect1>
 686                 <title>Example 6</title>
 687
 688                 <programlisting># chcon system_u:object_r:svirt_sandbox_file_t:s0:c0,c1 -R /srv/container
 689 # systemd-nspawn -L system_u:object_r:svirt_sandbox_file_t:s0:c0,c1 -Z system_u:system_r:svirt_lxc_net_t:s0:c0,c1 -D /srv/container /bin/sh</programlisting>
 690
 691                 <para>This runs a container with SELinux sandbox security contexts.</para>
 692         </refsect1>
 693
 694         <refsect1>
 695                 <title>Exit status</title>
 696
 697                 <para>The exit code of the program executed in the
 698                 container is returned.</para>
 699         </refsect1>
 700
 701         <refsect1>
 702                 <title>See Also</title>
 703                 <para>
 704                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 705                         <citerefentry><refentrytitle>chroot</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 706                         <citerefentry><refentrytitle>yum</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 707                         <citerefentry><refentrytitle>debootstrap</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 708                         <citerefentry><refentrytitle>pacman</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 709                         <citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 710                         <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 711                 </para>
 712         </refsect1>
 713
 714 </refentry>