summaryrefslogtreecommitdiff
path: root/man/systemd-detect-virt.xml
blob: 1f5270dbb2a49f4d4eaf57281151f1748e7b299d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
<?xml version='1.0'?> <!--*-nxml-*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
  "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">

<!--
  SPDX-License-Identifier: LGPL-2.1+
-->

<refentry id="systemd-detect-virt"
          xmlns:xi="http://www.w3.org/2001/XInclude">

  <refentryinfo>
    <title>systemd-detect-virt</title>
    <productname>systemd</productname>
  </refentryinfo>

  <refmeta>
    <refentrytitle>systemd-detect-virt</refentrytitle>
    <manvolnum>1</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>systemd-detect-virt</refname>
    <refpurpose>Detect execution in a virtualized environment</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <cmdsynopsis>
      <command>systemd-detect-virt</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
    </cmdsynopsis>
  </refsynopsisdiv>

  <refsect1>
    <title>Description</title>

    <para><command>systemd-detect-virt</command> detects execution in
    a virtualized environment. It identifies the virtualization
    technology and can distinguish full machine virtualization from
    container virtualization. <filename>systemd-detect-virt</filename>
    exits with a return value of 0 (success) if a virtualization
    technology is detected, and non-zero (error) otherwise. By default,
    any type of virtualization is detected, and the options
    <option>--container</option> and <option>--vm</option> can be used
    to limit what types of virtualization are detected.</para>

    <para>When executed without <option>--quiet</option> will print a
    short identifier for the detected virtualization technology. The
    following technologies are currently identified:</para>

    <table>
      <title>Known virtualization technologies (both
      VM, i.e. full hardware virtualization,
      and container, i.e. shared kernel virtualization)</title>
      <tgroup cols='3' align='left' colsep='1' rowsep='1'>
        <colspec colname="type" />
        <colspec colname="id" />
        <colspec colname="product" />
        <thead>
          <row>
            <entry>Type</entry>
            <entry>ID</entry>
            <entry>Product</entry>
          </row>
        </thead>
        <tbody>
          <row>
            <entry valign="top" morerows="11">VM</entry>
            <entry><varname>qemu</varname></entry>
            <entry>QEMU software virtualization, without KVM</entry>
          </row>

          <row>
            <entry><varname>kvm</varname></entry>
            <entry>Linux KVM kernel virtual machine, with whatever software, except Oracle Virtualbox</entry>
          </row>

          <row>
            <entry><varname>zvm</varname></entry>
            <entry>s390 z/VM</entry>
          </row>

          <row>
            <entry><varname>vmware</varname></entry>
            <entry>VMware Workstation or Server, and related products</entry>
          </row>

          <row>
            <entry><varname>microsoft</varname></entry>
            <entry>Hyper-V, also known as Viridian or Windows Server Virtualization</entry>
          </row>

          <row>
            <entry><varname>oracle</varname></entry>
            <entry>Oracle VM VirtualBox (historically marketed by innotek and Sun Microsystems), for legacy and KVM hypervisor</entry>
          </row>

          <row>
            <entry><varname>xen</varname></entry>
            <entry>Xen hypervisor (only domU, not dom0)</entry>
          </row>

          <row>
            <entry><varname>bochs</varname></entry>
            <entry>Bochs Emulator</entry>
          </row>

          <row>
            <entry><varname>uml</varname></entry>
            <entry>User-mode Linux</entry>
          </row>

          <row>
            <entry><varname>parallels</varname></entry>
            <entry>Parallels Desktop, Parallels Server</entry>
          </row>

          <row>
            <entry><varname>bhyve</varname></entry>
            <entry>bhyve, FreeBSD hypervisor</entry>
          </row>

          <row>
            <entry><varname>qnx</varname></entry>
            <entry>QNX hypervisor</entry>
          </row>

          <row>
            <entry><varname>acrn</varname></entry>
            <entry><ulink url="https://projectacrn.org">ACRN hypervisor</ulink></entry>
          </row>

          <row>
            <entry valign="top" morerows="6">Container</entry>
            <entry><varname>openvz</varname></entry>
            <entry>OpenVZ/Virtuozzo</entry>
          </row>

          <row>
            <entry><varname>lxc</varname></entry>
            <entry>Linux container implementation by LXC</entry>
          </row>

          <row>
            <entry><varname>lxc-libvirt</varname></entry>
            <entry>Linux container implementation by libvirt</entry>
          </row>

          <row>
            <entry><varname>systemd-nspawn</varname></entry>
            <entry>systemd's minimal container implementation, see <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry></entry>
          </row>

          <row>
            <entry><varname>docker</varname></entry>
            <entry>Docker container manager</entry>
          </row>

          <row>
            <entry><varname>rkt</varname></entry>
            <entry>rkt app container runtime</entry>
          </row>

          <row>
            <entry><varname>wsl</varname></entry>
            <entry><ulink url="https://docs.microsoft.com/en-us/windows/wsl/about">Windows Subsystem for Linux</ulink></entry>
          </row>
        </tbody>
      </tgroup>
    </table>

    <para>If multiple virtualization solutions are used, only the
    "innermost" is detected and identified. That means if both
    machine and container virtualization are used in
    conjunction, only the latter will be identified (unless
    <option>--vm</option> is passed).</para>
    <para> Windows Subsystem for Linux is not a Linux container,
    but an environment for running Linux userspace applications on
    top of the Windows kernel using a Linux-compatible interface.
    WSL is categorized as a container for practical purposes.
    Multiple WSL environments share the same kernel and services
    should generally behave like when being run in a container.</para>
  </refsect1>

  <refsect1>
    <title>Options</title>

    <para>The following options are understood:</para>

    <variablelist>
      <varlistentry>
        <term><option>-c</option></term>
        <term><option>--container</option></term>

        <listitem><para>Only detects container virtualization (i.e.
        shared kernel virtualization).</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>-v</option></term>
        <term><option>--vm</option></term>

        <listitem><para>Only detects hardware virtualization.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>-r</option></term>
        <term><option>--chroot</option></term>

        <listitem><para>Detect whether invoked in a
        <citerefentry><refentrytitle>chroot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
        environment. In this mode, no output is written, but the return
        value indicates whether the process was invoked in a
        <function>chroot()</function>
        environment or not.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--private-users</option></term>

        <listitem><para>Detect whether invoked in a user namespace.  In this mode, no
        output is written, but the return value indicates whether the process was invoked
        inside of a user namespace or not. See
        <citerefentry project='man-pages'><refentrytitle>user_namespaces</refentrytitle><manvolnum>7</manvolnum></citerefentry>
        for more information.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>-q</option></term>
        <term><option>--quiet</option></term>

        <listitem><para>Suppress output of the virtualization
        technology identifier.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--list</option></term>

        <listitem><para>Output all currently known and detectable container and VM environments.</para></listitem>
      </varlistentry>

      <xi:include href="standard-options.xml" xpointer="help" />
      <xi:include href="standard-options.xml" xpointer="version" />
    </variablelist>

  </refsect1>

  <refsect1>
    <title>Exit status</title>

    <para>If a virtualization technology is detected, 0 is returned, a
    non-zero code otherwise.</para>
  </refsect1>

  <refsect1>
    <title>See Also</title>
    <para>
      <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>chroot</refentrytitle><manvolnum>2</manvolnum></citerefentry>,
      <citerefentry project='man-pages'><refentrytitle>namespaces</refentrytitle><manvolnum>7</manvolnum></citerefentry>
    </para>
  </refsect1>

</refentry>