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     project='man-pages'><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>, but it
  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     fds must be passed with the names <literal>kvm</literal> and <literal>vhost-vsock</literal> respectively.</para>
  43
  44     <para>Note: on Ubuntu/Debian derivatives systemd-vmspawn requires the user to be in the <literal>kvm</literal> group to use the VSock options.</para>
  45   </refsect1>
  46
  47   <refsect1>
  48     <title>Options</title>
  49
  50     <para>The excess arguments are passed as extra kernel command line arguments using SMBIOS.</para>
  51
  52     <para>The following options are understood:</para>
  53
  54     <variablelist>
  55
  56       <varlistentry>
  57         <term><option>-q</option></term>
  58         <term><option>--quiet</option></term>
  59
  60         <listitem><para>Turns off any status output by the tool
  61         itself. When this switch is used, the only output from vmspawn
  62         will be the console output of the Virtual Machine OS itself.</para>
  63
  64         <xi:include href="version-info.xml" xpointer="v256"/></listitem>
  65       </varlistentry>
  66
  67     </variablelist>
  68
  69     <refsect2>
  70       <title>Image Options</title>
  71
  72       <varlistentry>
  73         <term><option>-D</option></term>
  74         <term><option>--directory=</option></term>
  75
  76         <listitem><para>Directory to use as file system root for the virtual machine.</para>
  77
  78         <para>One of either <option>--directory=</option> or <option>--image=</option> must be specified.</para>
  79         <para>Note: If mounting a non-root owned directory you may require <option>--private-users=</option>
  80               to map into the user's subuid namespace.</para>
  81
  82         <xi:include href="version-info.xml" xpointer="v256"/>
  83         </listitem>
  84       </varlistentry>
  85
  86       <variablelist>
  87         <varlistentry>
  88           <term><option>-i</option></term>
  89           <term><option>--image=</option></term>
  90
  91           <listitem><para>Root file system disk image (or device node) for the virtual machine.</para>
  92
  93           <xi:include href="version-info.xml" xpointer="v255"/>
  94           </listitem>
  95         </varlistentry>
  96       </variablelist>
  97     </refsect2>
  98
  99     <refsect2>
 100       <title>Host Configuration</title>
 101
 102       <variablelist>
 103         <varlistentry>
 104           <term><option>--qemu-smp=</option><replaceable>SMP</replaceable></term>
 105
 106           <listitem><para>Configures the number of CPUs to start the virtual machine with.
 107           Defaults to 1.</para>
 108
 109           <xi:include href="version-info.xml" xpointer="v255"/>
 110           </listitem>
 111         </varlistentry>
 112
 113         <varlistentry>
 114           <term><option>--qemu-mem=</option><replaceable>MEM</replaceable></term>
 115
 116           <listitem><para>Configures the amount of memory to start the virtual machine with.
 117           Defaults to 2G.</para>
 118
 119           <xi:include href="version-info.xml" xpointer="v255"/>
 120           </listitem>
 121         </varlistentry>
 122
 123       <varlistentry>
 124         <term><option>--qemu-kvm=</option><replaceable>BOOL</replaceable></term>
 125
 126         <listitem><para>Configures whether to use KVM. If the option is not specified KVM support will be
 127         detected automatically. If true, KVM is always used, and if false, KVM is never used.</para>
 128
 129         <xi:include href="version-info.xml" xpointer="v255"/></listitem>
 130       </varlistentry>
 131
 132       <varlistentry>
 133         <term><option>--qemu-vsock=</option><replaceable>BOOL</replaceable></term>
 134
 135         <listitem>
 136           <para>Configure whether to use VSock networking.</para>
 137           <para>If the option is not specified VSock support will be detected automatically.
 138           If yes is specified VSocks are always used, and vice versa if no is set VSocks are never used.</para>
 139           <xi:include href="version-info.xml" xpointer="v255"/>
 140         </listitem>
 141       </varlistentry>
 142
 143       <varlistentry>
 144         <term><option>--vsock-cid=</option><replaceable>CID</replaceable></term>
 145
 146         <listitem>
 147           <para>Configure vmspawn to use a specific CID for the guest.</para>
 148           <para>If the option is not specified or an empty argument is supplied the guest will be assigned a random CID.</para>
 149           <para>Valid CIDs are in the range <constant>3</constant> to <constant>4294967294</constant> (<constant>0xFFFF_FFFE</constant>).
 150           CIDs outside of this range are reserved.</para>
 151           <xi:include href="version-info.xml" xpointer="v255"/>
 152         </listitem>
 153       </varlistentry>
 154
 155       <varlistentry>
 156         <term><option>--tpm=</option><replaceable>BOOL</replaceable></term>
 157
 158         <listitem>
 159           <para>Configure whether to use qemu with a virtual TPM or not.</para>
 160           <para>If the option is not specified vmspawn will detect the presence of <citerefentry project='man-pages'>
 161           <refentrytitle>swtpm</refentrytitle><manvolnum>8</manvolnum></citerefentry> and use it if available.
 162           If yes is specified <citerefentry project='man-pages'><refentrytitle>swtpm</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 163           is always used, and vice versa if no is set <citerefentry project='man-pages'><refentrytitle>swtpm</refentrytitle>
 164           <manvolnum>8</manvolnum></citerefentry> is never used.</para>
 165           <para>Note: the virtual TPM used may change in future.</para>
 166           <xi:include href="version-info.xml" xpointer="v256"/>
 167         </listitem>
 168       </varlistentry>
 169
 170       <varlistentry>
 171         <term><option>--linux=</option><replaceable>PATH</replaceable></term>
 172
 173         <listitem>
 174           <para>Set the linux kernel image to use for direct kernel boot.</para>
 175           <para>If no kernel was installed into the image then the image will fail to boot.</para>
 176           <xi:include href="version-info.xml" xpointer="v256"/>
 177         </listitem>
 178       </varlistentry>
 179
 180       <varlistentry>
 181         <term><option>--initrd=</option><replaceable>PATH</replaceable></term>
 182
 183         <listitem>
 184           <para>Set the initrd to use for direct kernel boot.</para>
 185           <para>If the linux kernel supplied is a UKI then this argument is not required.</para>
 186           <para>If the option is specified multiple times vmspawn will merge the initrds together.</para>
 187           <para>If no initrd was installed into the image then the image will fail to boot.</para>
 188           <xi:include href="version-info.xml" xpointer="v256"/>
 189         </listitem>
 190       </varlistentry>
 191
 192       <varlistentry>
 193         <term><option>--qemu-gui</option></term>
 194
 195         <listitem><para>Start QEMU in graphical mode.</para>
 196
 197         <xi:include href="version-info.xml" xpointer="v255"/></listitem>
 198       </varlistentry>
 199
 200       <varlistentry>
 201         <term><option>-n</option></term>
 202         <term><option>--network-tap</option></term>
 203
 204         <listitem>
 205           <para>Create a TAP device to network with the virtual machine.</para>
 206           <para>
 207             Note: root privileges are required to use TAP networking.
 208             Additionally requires a correctly setup
 209             <citerefentry><refentrytitle>systemd-networkd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
 210             to be running on the host to ensure the host interface is correctly configured.
 211             The relevant <literal>.network</literal> file can be found at <filename>/usr/lib/systemd/network/80-vm-vt.network</filename>.
 212           </para>
 213           <xi:include href="version-info.xml" xpointer="v255"/>
 214         </listitem>
 215       </varlistentry>
 216
 217       <varlistentry>
 218         <term><option>--network-user-mode</option></term>
 219
 220         <listitem><para>Use user mode networking with QEMU.</para>
 221
 222         <xi:include href="version-info.xml" xpointer="v255"/></listitem>
 223       </varlistentry>
 224
 225       <varlistentry>
 226         <term><option>--firmware=</option><replaceable>PATH</replaceable></term>
 227
 228         <listitem><para>Takes an absolute path, or a relative path beginning with
 229         <filename>./</filename>. Specifies a JSON firmware definition file, which allows selecting the
 230         firmware to boot in the VM. If not specified a suitable firmware is automatically discovered. If the
 231         special string <literal>list</literal> is specified lists all discovered firmwares.</para>
 232
 233         <xi:include href="version-info.xml" xpointer="v256"/></listitem>
 234       </varlistentry>
 235
 236       <varlistentry>
 237         <term><option>--secure-boot=</option><replaceable>BOOL</replaceable></term>
 238
 239         <listitem><para>Configure whether to search for firmware which supports Secure Boot.</para>
 240         <para>If the option is not specified the first firmware which is detected will be used.
 241         If the option is set to yes then the first firmware with Secure Boot support will be selected.
 242         If no is specified then the first firmware without Secure Boot will be selected.</para>
 243
 244         <xi:include href="version-info.xml" xpointer="v255"/></listitem>
 245       </varlistentry>
 246       </variablelist>
 247     </refsect2>
 248
 249     <refsect2>
 250       <title>System Identity Options</title>
 251
 252       <variablelist>
 253         <varlistentry>
 254           <term><option>-M</option></term>
 255           <term><option>--machine=</option></term>
 256
 257           <listitem><para>Sets the machine name for this virtual machine. This
 258           name may be used to identify this virtual machine during its runtime
 259           (for example in tools like
 260           <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 261           and similar).</para>
 262           <xi:include href="version-info.xml" xpointer="v255"/>
 263           </listitem>
 264         </varlistentry>
 265       </variablelist>
 266     </refsect2>
 267
 268     <refsect2>
 269       <title>User Namespacing Options</title>
 270
 271       <variablelist>
 272         <varlistentry>
 273           <term><option>--private-users=</option><replaceable>UID_SHIFT[:UID_RANGE]</replaceable></term>
 274
 275           <listitem><para>Controls user namespacing under <option>--directory=</option>.
 276           If enabled, <citerefentry project='man-pages'><refentrytitle>virtiofsd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 277           is instructed to map user and group ids (UIDs and GIDs). This involves mapping the private UIDs/GIDs used in the virtual machine
 278           (starting with the virtual machine's root user 0 and up) to a range of UIDs/GIDs on the host that are not used for other
 279           purposes (usually in the range beyond the host's UID/GID 65536).</para>
 280
 281           <para>If one or two colon-separated numbers are specified, user namespacing is turned on. <replaceable>UID_SHIFT</replaceable>
 282           specifies the first host UID/GID to map, <replaceable>UID_RANGE</replaceable> is optional and specifies number of host
 283           UIDs/GIDs to assign to the virtual machine. If <replaceable>UID_RANGE</replaceable> is omitted, 65536 UIDs/GIDs are assigned.</para>
 284
 285           <para>When user namespaces are used, the GID range assigned to each virtual machine is always chosen identical to the
 286           UID range.</para>
 287
 288           <xi:include href="version-info.xml" xpointer="v256"/></listitem>
 289         </varlistentry>
 290       </variablelist>
 291     </refsect2>
 292
 293     <refsect2>
 294       <title>Mount Options</title>
 295
 296       <variablelist>
 297
 298         <varlistentry>
 299           <term><option>--bind=</option><replaceable>PATH</replaceable></term>
 300           <term><option>--bind-ro=</option><replaceable>PATH</replaceable></term>
 301
 302           <listitem><para>Mount a directory from the host into the virtual machine. Takes one of: a path
 303           argument — in which case the specified path will be mounted from the host to the same path in the virtual machine, or
 304           a colon-separated pair of paths — in which case the first specified path is the source in the host, and the
 305           second path is the destination in the virtual machine. If the source path is not absolute, it is resolved
 306           relative to the current working directory. The <option>--bind-ro=</option> option creates read-only bind mounts.
 307           Backslash escapes are interpreted, so <literal>\:</literal> may be used to embed colons in either path.
 308           This option may be specified multiple times for creating multiple independent bind mount points.</para>
 309
 310           <xi:include href="version-info.xml" xpointer="v256"/></listitem>
 311         </varlistentry>
 312       </variablelist>
 313     </refsect2>
 314
 315     <refsect2>
 316       <title>Credentials</title>
 317
 318       <variablelist>
 319         <varlistentry>
 320           <term><option>--load-credential=</option><replaceable>ID</replaceable>:<replaceable>PATH</replaceable></term>
 321           <term><option>--set-credential=</option><replaceable>ID</replaceable>:<replaceable>VALUE</replaceable></term>
 322
 323           <listitem><para>Pass a credential to the virtual machine. These two options correspond to the
 324           <varname>LoadCredential=</varname> and <varname>SetCredential=</varname> settings in unit files. See
 325           <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
 326           details about these concepts, as well as the syntax of the option's arguments.</para>
 327
 328           <para>In order to embed binary data into the credential data for <option>--set-credential=</option>,
 329           use C-style escaping (i.e. <literal>\n</literal> to embed a newline, or <literal>\x00</literal> to
 330           embed a <constant>NUL</constant> byte). Note that the invoking shell might already apply unescaping
 331           once, hence this might require double escaping!.</para>
 332
 333           <xi:include href="version-info.xml" xpointer="v255"/></listitem>
 334         </varlistentry>
 335       </variablelist>
 336
 337     </refsect2><refsect2>
 338       <title>Other</title>
 339
 340       <variablelist>
 341         <xi:include href="standard-options.xml" xpointer="no-pager" />
 342         <xi:include href="standard-options.xml" xpointer="help" />
 343         <xi:include href="standard-options.xml" xpointer="version" />
 344       </variablelist>
 345     </refsect2>
 346   </refsect1>
 347
 348   <xi:include href="common-variables.xml" />
 349
 350   <refsect1>
 351     <title>Examples</title>
 352
 353     <example>
 354       <title>Run an Arch Linux VM image generated by mkosi</title>
 355
 356       <programlisting>
 357 $ mkosi -d arch -p systemd -p linux --autologin -o image.raw -f build
 358 $ systemd-vmspawn --image=image.raw
 359       </programlisting>
 360     </example>
 361   </refsect1>
 362
 363   <refsect1>
 364     <title>Exit status</title>
 365
 366     <para>If an error occurred the value errno is propagated to the return code.
 367     If EXIT_STATUS is supplied by the running image that is returned.
 368     Otherwise EXIT_SUCCESS is returned.</para>
 369   </refsect1>
 370
 371   <refsect1>
 372     <title>See Also</title>
 373     <para><simplelist type="inline">
 374       <member><citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
 375       <member><citerefentry><refentrytitle>mkosi</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
 376     </simplelist></para>
 377   </refsect1>
 378 </refentry>