man/systemd-vmspawn.xml

   1 <?xml version='1.0'?>
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
   4 <!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
   5
   6 <refentry id="systemd-vmspawn" conditional="ENABLE_VMSPAWN"
   7     xmlns:xi="http://www.w3.org/2001/XInclude">
   8
   9   <refentryinfo>
  10     <title>systemd-vmspawn</title>
  11     <productname>systemd</productname>
  12   </refentryinfo>
  13
  14   <refmeta>
  15     <refentrytitle>systemd-vmspawn</refentrytitle>
  16     <manvolnum>1</manvolnum>
  17   </refmeta>
  18
  19   <refnamediv>
  20     <refname>systemd-vmspawn</refname>
  21     <refpurpose>Spawn an OS in a virtual machine</refpurpose>
  22   </refnamediv>
  23
  24   <refsynopsisdiv>
  25     <cmdsynopsis>
  26       <command>systemd-vmspawn</command>
  27       <arg choice="opt" rep="repeat">OPTIONS</arg>
  28       <arg choice="opt" rep="repeat">ARGS</arg>
  29     </cmdsynopsis>
  30   </refsynopsisdiv>
  31
  32   <refsect1>
  33     <title>Description</title>
  34     <para><command>systemd-vmspawn</command> may be used to start a virtual machine from an OS image. In many ways it is similar to <citerefentry>
  35     <refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>, but
  36     launches a full virtual machine instead of using namespaces.</para>
  37
  38     <para>File descriptors for <filename>/dev/kvm</filename> and <filename>/dev/vhost-vsock</filename> can be
  39     passed to <command>systemd-vmspawn</command> via systemd's native socket passing interface (see
  40     <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry> for
  41     details about the precise protocol used and the order in which the file descriptors are passed), these
  42     file descriptors must be passed with the names <literal>kvm</literal> and <literal>vhost-vsock</literal>
  43     respectively.</para>
  44
  45     <para>Note: on Ubuntu/Debian derivatives systemd-vmspawn requires the user to be in the
  46     <literal>kvm</literal> group to use the VSOCK options.</para>
  47   </refsect1>
  48
  49   <refsect1>
  50     <title>Options</title>
  51
  52     <para>The excess arguments are passed as extra kernel command line arguments using SMBIOS.</para>
  53
  54     <para>The following options are understood:</para>
  55
  56     <variablelist>
  57
  58       <varlistentry>
  59         <term><option>-q</option></term>
  60         <term><option>--quiet</option></term>
  61
  62         <listitem><para>Turns off any status output by the tool
  63         itself. When this switch is used, the only output from vmspawn
  64         will be the console output of the Virtual Machine OS itself.</para>
  65
  66         <xi:include href="version-info.xml" xpointer="v256"/></listitem>
  67       </varlistentry>
  68
  69     </variablelist>
  70
  71     <refsect2>
  72       <title>Image Options</title>
  73
  74       <varlistentry>
  75         <term><option>-D</option></term>
  76         <term><option>--directory=</option></term>
  77
  78         <listitem><para>Directory to use as file system root for the virtual machine.</para>
  79
  80         <para>One of either <option>--directory=</option> or <option>--image=</option> must be specified.</para>
  81
  82         <para>Note: If mounting a non-root owned directory you may require <option>--private-users=</option>
  83               to map into the user's subuid namespace.</para>
  84
  85         <xi:include href="version-info.xml" xpointer="v256"/>
  86         </listitem>
  87       </varlistentry>
  88
  89       <variablelist>
  90         <varlistentry>
  91           <term><option>-i</option></term>
  92           <term><option>--image=</option></term>
  93
  94           <listitem><para>Root file system disk image (or device node) for the virtual machine.</para>
  95
  96           <xi:include href="version-info.xml" xpointer="v255"/>
  97           </listitem>
  98         </varlistentry>
  99       </variablelist>
 100     </refsect2>
 101
 102     <refsect2>
 103       <title>Host Configuration</title>
 104
 105       <variablelist>
 106         <varlistentry>
 107           <term><option>--cpus=<replaceable>CPUS</replaceable></option></term>
 108
 109           <listitem><para>Configures the number of CPUs to start the virtual machine with.
 110           Defaults to 1.</para>
 111
 112           <xi:include href="version-info.xml" xpointer="v255"/>
 113           </listitem>
 114         </varlistentry>
 115
 116         <varlistentry>
 117           <term><option>--ram=<replaceable>BYTES</replaceable></option></term>
 118
 119           <listitem><para>Configures the amount of memory to start the virtual machine with.
 120           Defaults to 2G.</para>
 121
 122           <xi:include href="version-info.xml" xpointer="v255"/>
 123           </listitem>
 124         </varlistentry>
 125
 126         <varlistentry>
 127           <term><option>--kvm=<replaceable>BOOL</replaceable></option></term>
 128
 129           <listitem><para>Configures whether to use KVM. If the option is not specified KVM support will be
 130           detected automatically. If true, KVM is always used, and if false, KVM is never used.</para>
 131
 132           <xi:include href="version-info.xml" xpointer="v255"/></listitem>
 133         </varlistentry>
 134
 135         <varlistentry>
 136           <term><option>--vsock=<replaceable>BOOL</replaceable></option></term>
 137
 138           <listitem>
 139             <para>Configure whether to use VSOCK networking.</para>
 140
 141             <para>If the option is not specified VSOCK support will be detected automatically.  If yes is
 142             specified VSOCK is always used, and vice versa if no is set VSOCK are never used.</para>
 143             <xi:include href="version-info.xml" xpointer="v255"/>
 144           </listitem>
 145         </varlistentry>
 146
 147         <varlistentry>
 148           <term><option>--vsock-cid=<replaceable>CID</replaceable></option></term>
 149
 150           <listitem>
 151             <para>Configure vmspawn to use a specific CID for the guest.</para>
 152
 153             <para>If the option is not specified or an empty argument is supplied the guest will be assigned a random CID.</para>
 154
 155             <para>Valid CIDs are in the range <constant>3</constant> to <constant>4294967294</constant> (<constant>0xFFFF_FFFE</constant>).
 156             CIDs outside of this range are reserved.</para>
 157
 158             <xi:include href="version-info.xml" xpointer="v255"/>
 159           </listitem>
 160         </varlistentry>
 161
 162         <varlistentry>
 163           <term><option>--tpm=<replaceable>BOOL</replaceable></option></term>
 164
 165           <listitem>
 166             <para>Configure whether to use VM with a virtual TPM or not.</para>
 167
 168             <para>If the option is not specified vmspawn will detect the presence of <citerefentry project='debian'>
 169             <refentrytitle>swtpm</refentrytitle><manvolnum>8</manvolnum></citerefentry> and use it if available.
 170             If yes is specified <citerefentry project='debian'><refentrytitle>swtpm</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 171             is always used, and vice versa if no is set <citerefentry project='debian'><refentrytitle>swtpm</refentrytitle>
 172             <manvolnum>8</manvolnum></citerefentry> is never used.</para>
 173
 174             <para>Note: the virtual TPM used may change in future.</para>
 175
 176             <xi:include href="version-info.xml" xpointer="v256"/>
 177           </listitem>
 178         </varlistentry>
 179
 180         <varlistentry>
 181           <term><option>--linux=<replaceable>PATH</replaceable></option></term>
 182
 183           <listitem>
 184             <para>Set the linux kernel image to use for direct kernel boot.</para>
 185
 186             <para>If no kernel was installed into the image then the image will fail to boot.</para>
 187
 188             <xi:include href="version-info.xml" xpointer="v256"/>
 189           </listitem>
 190         </varlistentry>
 191
 192         <varlistentry>
 193           <term><option>--initrd=<replaceable>PATH</replaceable></option></term>
 194
 195           <listitem>
 196             <para>Set the initrd to use for direct kernel boot.</para>
 197
 198             <para>If the linux kernel supplied is a UKI then this argument is not required.</para>
 199
 200             <para>If the option is specified multiple times vmspawn will merge the initrds together.</para>
 201
 202             <para>If no initrd was installed into the image then the image will fail to boot.</para>
 203
 204             <xi:include href="version-info.xml" xpointer="v256"/>
 205           </listitem>
 206         </varlistentry>
 207
 208         <varlistentry>
 209           <term><option>-n</option></term>
 210           <term><option>--network-tap</option></term>
 211
 212           <listitem>
 213             <para>Create a TAP device to network with the virtual machine.</para>
 214
 215             <para>Note: root privileges are required to use TAP networking.
 216             Additionally,
 217             <citerefentry><refentrytitle>systemd-networkd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 218             must be running and correctly set up on the host to provision the host interface. The relevant
 219             <literal>.network</literal> file can be found at
 220             <filename>/usr/lib/systemd/network/80-vm-vt.network</filename>.
 221             </para>
 222
 223             <xi:include href="version-info.xml" xpointer="v255"/>
 224           </listitem>
 225         </varlistentry>
 226
 227         <varlistentry>
 228           <term><option>--network-user-mode</option></term>
 229
 230           <listitem><para>Use user mode networking.</para>
 231
 232           <xi:include href="version-info.xml" xpointer="v255"/></listitem>
 233         </varlistentry>
 234
 235         <varlistentry>
 236           <term><option>--firmware=<replaceable>PATH</replaceable></option></term>
 237
 238           <listitem><para>Takes an absolute path, or a relative path beginning with
 239           <filename>./</filename>. Specifies a JSON firmware definition file, which allows selecting the
 240           firmware to boot in the VM. If not specified a suitable firmware is automatically discovered. If the
 241           special string <literal>list</literal> is specified lists all discovered firmwares.</para>
 242
 243           <xi:include href="version-info.xml" xpointer="v256"/></listitem>
 244         </varlistentry>
 245
 246         <varlistentry>
 247           <term><option>--discard-disk=<replaceable>BOOL</replaceable></option></term>
 248
 249           <listitem><para>Controls whether qemu processes discard requests from the VM.
 250           This prevents long running VMs from using more disk space than required.
 251           This is enabled by default.</para>
 252
 253           <xi:include href="version-info.xml" xpointer="v256"/></listitem>
 254         </varlistentry>
 255
 256         <varlistentry>
 257           <term><option>--secure-boot=<replaceable>BOOL</replaceable></option></term>
 258
 259           <listitem><para>Configure whether to search for firmware which supports Secure Boot.</para>
 260
 261           <para>If the option is not specified the first firmware which is detected will be used.
 262           If the option is set to yes then the first firmware with Secure Boot support will be selected.
 263           If no is specified then the first firmware without Secure Boot will be selected.</para>
 264
 265           <xi:include href="version-info.xml" xpointer="v255"/></listitem>
 266         </varlistentry>
 267       </variablelist>
 268     </refsect2>
 269
 270     <refsect2>
 271       <title>System Identity Options</title>
 272
 273       <variablelist>
 274         <varlistentry>
 275           <term><option>-M</option></term>
 276           <term><option>--machine=</option></term>
 277
 278           <listitem><para>Sets the machine name for this virtual machine. This
 279           name may be used to identify this virtual machine during its runtime
 280           (for example in tools like
 281           <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 282           and similar).</para>
 283
 284           <xi:include href="version-info.xml" xpointer="v255"/>
 285           </listitem>
 286         </varlistentry>
 287
 288         <varlistentry>
 289           <term><option>--uuid=</option></term>
 290
 291           <listitem><para>Set the specified UUID for the virtual machine. The
 292           init system will initialize
 293           <filename>/etc/machine-id</filename> from this if this file is
 294           not set yet. Note that this option takes effect only if
 295           <filename>/etc/machine-id</filename> in the virtual machine is
 296           unpopulated.</para>
 297
 298           <xi:include href="version-info.xml" xpointer="v256"/></listitem>
 299         </varlistentry>
 300       </variablelist>
 301     </refsect2>
 302
 303     <refsect2>
 304       <title>Property Options</title>
 305
 306       <variablelist>
 307         <varlistentry>
 308           <term><option>--register=</option></term>
 309
 310           <listitem><para>Controls whether the virtual machine is registered with
 311           <citerefentry><refentrytitle>systemd-machined</refentrytitle><manvolnum>8</manvolnum></citerefentry>.  Takes a
 312           boolean argument, which defaults to <literal>yes</literal> when running as root, and <literal>no</literal> when
 313           running as a regular user.  This ensures that the virtual machine is accessible via
 314           <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para>
 315
 316           <para>Note: root privileges are required to use this option as registering with
 317           <citerefentry><refentrytitle>systemd-machined</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 318           requires privileged D-Bus method calls.</para>
 319
 320           <xi:include href="version-info.xml" xpointer="v256"/></listitem>
 321         </varlistentry>
 322       </variablelist>
 323     </refsect2>
 324
 325     <refsect2>
 326       <title>User Namespacing Options</title>
 327
 328       <variablelist>
 329         <varlistentry>
 330           <term><option>--private-users=<replaceable>UID_SHIFT[:UID_RANGE]</replaceable></option></term>
 331
 332           <listitem><para>Controls user namespacing under <option>--directory=</option>.
 333           If enabled, <command>virtiofsd</command> is instructed to map user and group ids (UIDs and GIDs).
 334           This involves mapping the private UIDs/GIDs used in the virtual machine (starting with the virtual machine's
 335           root user 0 and up) to a range of UIDs/GIDs on the host that are not used for other purposes (usually in the
 336           range beyond the host's UID/GID 65536).</para>
 337
 338           <para>If one or two colon-separated numbers are specified, user namespacing is turned on. <replaceable>UID_SHIFT</replaceable>
 339           specifies the first host UID/GID to map, <replaceable>UID_RANGE</replaceable> is optional and specifies number of host
 340           UIDs/GIDs to assign to the virtual machine. If <replaceable>UID_RANGE</replaceable> is omitted, 65536 UIDs/GIDs are assigned.</para>
 341
 342           <para>When user namespaces are used, the GID range assigned to each virtual machine is always chosen identical to the
 343           UID range.</para>
 344
 345           <xi:include href="version-info.xml" xpointer="v256"/></listitem>
 346         </varlistentry>
 347       </variablelist>
 348     </refsect2>
 349
 350     <refsect2>
 351       <title>Mount Options</title>
 352
 353       <variablelist>
 354
 355         <varlistentry>
 356           <term><option>--bind=<replaceable>PATH</replaceable></option></term>
 357           <term><option>--bind-ro=<replaceable>PATH</replaceable></option></term>
 358
 359           <listitem><para>Mount a directory from the host into the virtual machine. Takes one of: a path
 360           argument — in which case the specified path will be mounted from the host to the same path in the virtual machine, or
 361           a colon-separated pair of paths — in which case the first specified path is the source in the host, and the
 362           second path is the destination in the virtual machine. If the source path is not absolute, it is resolved
 363           relative to the current working directory. The <option>--bind-ro=</option> option creates read-only bind mounts.
 364           Backslash escapes are interpreted, so <literal>\:</literal> may be used to embed colons in either path.
 365           This option may be specified multiple times for creating multiple independent bind mount points.</para>
 366
 367           <xi:include href="version-info.xml" xpointer="v256"/></listitem>
 368         </varlistentry>
 369
 370         <varlistentry>
 371           <term><option>--extra-drive=<replaceable>PATH</replaceable></option></term>
 372
 373           <listitem><para>Takes a disk image or block device on the host and supplies it to the virtual machine as another drive.</para>
 374
 375           <xi:include href="version-info.xml" xpointer="v256"/></listitem>
 376         </varlistentry>
 377
 378       </variablelist>
 379     </refsect2>
 380
 381     <refsect2>
 382       <title>Integration Options</title>
 383
 384       <variablelist>
 385         <varlistentry>
 386           <term><option>--forward-journal=<replaceable>FILE|DIR</replaceable></option></term>
 387
 388           <listitem><para>Forward the virtual machine's journal to the host.
 389           <citerefentry><refentrytitle>systemd-journal-remote</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 390           is currently used to receive the guest VM's forwarded journal entries. This option determines where
 391           this journal is saved on the host and has the same semantics as
 392           <option>-o</option>/<option>--output</option> described in
 393           <citerefentry><refentrytitle>systemd-journal-remote</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
 394
 395           <xi:include href="version-info.xml" xpointer="v256"/>
 396           </listitem>
 397         </varlistentry>
 398
 399         <varlistentry>
 400           <term><option>--pass-ssh-key=<replaceable>BOOL</replaceable></option></term>
 401
 402           <listitem><para>By default an SSH key is generated to allow <command>systemd-vmspawn</command> to open
 403           a D-Bus connection to the VM's systemd bus. Setting this to "no" will disable SSH key generation.</para>
 404
 405           <para>The generated keys are ephemeral. That is they are valid only for the current invocation of <command>systemd-vmspawn</command>,
 406           and are typically not persisted.</para>
 407
 408           <xi:include href="version-info.xml" xpointer="v256"/>
 409           </listitem>
 410         </varlistentry>
 411
 412         <varlistentry>
 413           <term><option>--ssh-key-type=<replaceable>TYPE</replaceable></option></term>
 414
 415           <listitem><para>Configures the type of SSH key to generate, see
 416           <citerefentry project="man-pages"><refentrytitle>ssh-keygen</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 417           for more information.</para>
 418
 419           <para>By default <literal>ed25519</literal> keys are generated, however <literal>rsa</literal> keys
 420           may also be useful if the VM has a particularly old version of <command>sshd</command></para>.
 421
 422           <xi:include href="version-info.xml" xpointer="v256"/>
 423           </listitem>
 424         </varlistentry>
 425       </variablelist>
 426     </refsect2>
 427
 428     <refsect2>
 429       <title>Input/Output Options</title>
 430
 431       <variablelist>
 432         <varlistentry>
 433           <term><option>--console=<replaceable>MODE</replaceable></option></term>
 434
 435           <listitem><para>Configures how to set up the console of the VM. Takes one of
 436           <literal>interactive</literal>, <literal>read-only</literal>, <literal>native</literal>,
 437           <literal>gui</literal>. Defaults to <literal>interactive</literal>. <literal>interactive</literal>
 438           provides an interactive terminal interface to the VM. <literal>read-only</literal> is similar, but
 439           is strictly read-only, i.e. does not accept any input from the user. <literal>native</literal> also
 440           provides a TTY-based interface, but uses qemu native implementation (which means the qemu monitor
 441           is available). <literal>gui</literal> shows the qemu graphical UI.</para>
 442
 443           <xi:include href="version-info.xml" xpointer="v256"/></listitem>
 444         </varlistentry>
 445
 446         <varlistentry>
 447           <term><option>--background=<replaceable>COLOR</replaceable></option></term>
 448
 449           <listitem><para>Change the terminal background color to the specified ANSI color as long as the VM
 450           runs. The color specified should be an ANSI X3.64 SGR background color, i.e. strings such as
 451           <literal>40</literal>, <literal>41</literal>, …, <literal>47</literal>, <literal>48;2;…</literal>,
 452           <literal>48;5;…</literal>. See <ulink
 453           url="https://en.wikipedia.org/wiki/ANSI_escape_code#SGR_(Select_Graphic_Rendition)_parameters">ANSI
 454           Escape Code (Wikipedia)</ulink> for details. Assign an empty string to disable any coloring. This
 455           only has an effect in <option>--console=interactive</option> and
 456           <option>--console=read-only</option> modes.</para>
 457
 458           <xi:include href="version-info.xml" xpointer="v256"/>
 459           </listitem>
 460         </varlistentry>
 461       </variablelist>
 462     </refsect2>
 463
 464     <refsect2>
 465       <title>Credentials</title>
 466
 467       <variablelist>
 468         <varlistentry>
 469           <term><option>--load-credential=<replaceable>ID</replaceable>:<replaceable>PATH</replaceable></option></term>
 470           <term><option>--set-credential=<replaceable>ID</replaceable>:<replaceable>VALUE</replaceable></option></term>
 471
 472           <listitem><para>Pass a credential to the virtual machine. These two options correspond to the
 473           <varname>LoadCredential=</varname> and <varname>SetCredential=</varname> settings in unit files. See
 474           <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
 475           details about these concepts, as well as the syntax of the option's arguments.</para>
 476
 477           <para>In order to embed binary data into the credential data for <option>--set-credential=</option>,
 478           use C-style escaping (i.e. <literal>\n</literal> to embed a newline, or <literal>\x00</literal> to
 479           embed a <constant>NUL</constant> byte). Note that the invoking shell might already apply unescaping
 480           once, hence this might require double escaping!</para>
 481
 482           <xi:include href="version-info.xml" xpointer="v255"/></listitem>
 483         </varlistentry>
 484       </variablelist>
 485
 486     </refsect2><refsect2>
 487       <title>Other</title>
 488
 489       <variablelist>
 490         <xi:include href="standard-options.xml" xpointer="no-pager" />
 491         <xi:include href="standard-options.xml" xpointer="help" />
 492         <xi:include href="standard-options.xml" xpointer="version" />
 493       </variablelist>
 494     </refsect2>
 495   </refsect1>
 496
 497   <xi:include href="common-variables.xml" />
 498
 499   <refsect1>
 500     <title>Examples</title>
 501
 502     <example>
 503       <title>Run an Arch Linux VM image generated by mkosi</title>
 504
 505       <programlisting>
 506 $ mkosi -d arch -p systemd -p linux --autologin -o image.raw -f build
 507 $ systemd-vmspawn --image=image.raw
 508       </programlisting>
 509     </example>
 510   </refsect1>
 511
 512   <refsect1>
 513     <title>Exit status</title>
 514
 515     <para>If an error occurred the value errno is propagated to the return code.
 516     If EXIT_STATUS is supplied by the running image that is returned.
 517     Otherwise EXIT_SUCCESS is returned.</para>
 518   </refsect1>
 519
 520   <refsect1>
 521     <title>See Also</title>
 522     <para><simplelist type="inline">
 523       <member><citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
 524       <member><citerefentry project='debian'><refentrytitle>mkosi</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
 525       <member><citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
 526       <member><citerefentry><refentrytitle>importctl</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
 527     </simplelist></para>
 528   </refsect1>
 529 </refentry>