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514094f9 | 1 | <?xml version='1.0'?> |
8f7a3c14 | 2 | <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" |
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3 | "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd" [ |
4 | <!ENTITY fedora_latest_version "28"> | |
5 | <!ENTITY fedora_cloud_release "1.1"> | |
6 | ]> | |
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7 | |
8 | <!-- | |
572eb058 | 9 | SPDX-License-Identifier: LGPL-2.1+ |
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10 | --> |
11 | ||
dfdebb1b | 12 | <refentry id="systemd-nspawn" |
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13 | xmlns:xi="http://www.w3.org/2001/XInclude"> |
14 | ||
15 | <refentryinfo> | |
16 | <title>systemd-nspawn</title> | |
17 | <productname>systemd</productname> | |
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18 | </refentryinfo> |
19 | ||
20 | <refmeta> | |
21 | <refentrytitle>systemd-nspawn</refentrytitle> | |
22 | <manvolnum>1</manvolnum> | |
23 | </refmeta> | |
24 | ||
25 | <refnamediv> | |
26 | <refname>systemd-nspawn</refname> | |
a7e2e50d | 27 | <refpurpose>Spawn a command or OS in a light-weight container</refpurpose> |
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28 | </refnamediv> |
29 | ||
30 | <refsynopsisdiv> | |
31 | <cmdsynopsis> | |
32 | <command>systemd-nspawn</command> | |
33 | <arg choice="opt" rep="repeat">OPTIONS</arg> | |
34 | <arg choice="opt"><replaceable>COMMAND</replaceable> | |
35 | <arg choice="opt" rep="repeat">ARGS</arg> | |
36 | </arg> | |
37 | </cmdsynopsis> | |
38 | <cmdsynopsis> | |
39 | <command>systemd-nspawn</command> | |
4447e799 | 40 | <arg choice="plain">--boot</arg> |
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41 | <arg choice="opt" rep="repeat">OPTIONS</arg> |
42 | <arg choice="opt" rep="repeat">ARGS</arg> | |
43 | </cmdsynopsis> | |
44 | </refsynopsisdiv> | |
45 | ||
46 | <refsect1> | |
47 | <title>Description</title> | |
48 | ||
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49 | <para><command>systemd-nspawn</command> may be used to run a command or OS in a light-weight namespace |
50 | container. In many ways it is similar to <citerefentry | |
51 | project='man-pages'><refentrytitle>chroot</refentrytitle><manvolnum>1</manvolnum></citerefentry>, but more powerful | |
52 | since it fully virtualizes the file system hierarchy, as well as the process tree, the various IPC subsystems and | |
53 | the host and domain name.</para> | |
54 | ||
5164c3b4 | 55 | <para><command>systemd-nspawn</command> may be invoked on any directory tree containing an operating system tree, |
b09c0bba | 56 | using the <option>--directory=</option> command line option. By using the <option>--machine=</option> option an OS |
5164c3b4 | 57 | tree is automatically searched for in a couple of locations, most importantly in |
a7e2e50d | 58 | <filename>/var/lib/machines</filename>, the suggested directory to place OS container images installed on the |
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59 | system.</para> |
60 | ||
61 | <para>In contrast to <citerefentry | |
62 | project='man-pages'><refentrytitle>chroot</refentrytitle><manvolnum>1</manvolnum></citerefentry> <command>systemd-nspawn</command> | |
63 | may be used to boot full Linux-based operating systems in a container.</para> | |
64 | ||
65 | <para><command>systemd-nspawn</command> limits access to various kernel interfaces in the container to read-only, | |
66 | such as <filename>/sys</filename>, <filename>/proc/sys</filename> or <filename>/sys/fs/selinux</filename>. The | |
67 | host's network interfaces and the system clock may not be changed from within the container. Device nodes may not | |
68 | be created. The host system cannot be rebooted and kernel modules may not be loaded from within the | |
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69 | container.</para> |
70 | ||
b09c0bba LP |
71 | <para>Use a tool like <citerefentry |
72 | project='mankier'><refentrytitle>dnf</refentrytitle><manvolnum>8</manvolnum></citerefentry>, <citerefentry | |
73 | project='die-net'><refentrytitle>debootstrap</refentrytitle><manvolnum>8</manvolnum></citerefentry>, or | |
74 | <citerefentry project='archlinux'><refentrytitle>pacman</refentrytitle><manvolnum>8</manvolnum></citerefentry> to | |
75 | set up an OS directory tree suitable as file system hierarchy for <command>systemd-nspawn</command> containers. See | |
76 | the Examples section below for details on suitable invocation of these commands.</para> | |
77 | ||
78 | <para>As a safety check <command>systemd-nspawn</command> will verify the existence of | |
79 | <filename>/usr/lib/os-release</filename> or <filename>/etc/os-release</filename> in the container tree before | |
80 | starting the container (see | |
81 | <citerefentry><refentrytitle>os-release</refentrytitle><manvolnum>5</manvolnum></citerefentry>). It might be | |
82 | necessary to add this file to the container tree manually if the OS of the container is too old to contain this | |
798d3a52 | 83 | file out-of-the-box.</para> |
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84 | |
85 | <para><command>systemd-nspawn</command> may be invoked directly from the interactive command line or run as system | |
86 | service in the background. In this mode each container instance runs as its own service instance; a default | |
87 | template unit file <filename>systemd-nspawn@.service</filename> is provided to make this easy, taking the container | |
88 | name as instance identifier. Note that different default options apply when <command>systemd-nspawn</command> is | |
6dd6a9c4 | 89 | invoked by the template unit file than interactively on the command line. Most importantly the template unit file |
b09c0bba | 90 | makes use of the <option>--boot</option> which is not the default in case <command>systemd-nspawn</command> is |
6dd6a9c4 | 91 | invoked from the interactive command line. Further differences with the defaults are documented along with the |
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92 | various supported options below.</para> |
93 | ||
94 | <para>The <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry> tool may | |
95 | be used to execute a number of operations on containers. In particular it provides easy-to-use commands to run | |
96 | containers as system services using the <filename>systemd-nspawn@.service</filename> template unit | |
97 | file.</para> | |
98 | ||
99 | <para>Along with each container a settings file with the <filename>.nspawn</filename> suffix may exist, containing | |
100 | additional settings to apply when running the container. See | |
101 | <citerefentry><refentrytitle>systemd.nspawn</refentrytitle><manvolnum>5</manvolnum></citerefentry> for | |
102 | details. Settings files override the default options used by the <filename>systemd-nspawn@.service</filename> | |
103 | template unit file, making it usually unnecessary to alter this template file directly.</para> | |
104 | ||
105 | <para>Note that <command>systemd-nspawn</command> will mount file systems private to the container to | |
106 | <filename>/dev</filename>, <filename>/run</filename> and similar. These will not be visible outside of the | |
107 | container, and their contents will be lost when the container exits.</para> | |
108 | ||
109 | <para>Note that running two <command>systemd-nspawn</command> containers from the same directory tree will not make | |
110 | processes in them see each other. The PID namespace separation of the two containers is complete and the containers | |
111 | will share very few runtime objects except for the underlying file system. Use | |
112 | <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s | |
113 | <command>login</command> or <command>shell</command> commands to request an additional login session in a running | |
114 | container.</para> | |
115 | ||
116 | <para><command>systemd-nspawn</command> implements the <ulink | |
28a0ad81 | 117 | url="https://www.freedesktop.org/wiki/Software/systemd/ContainerInterface">Container Interface</ulink> |
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118 | specification.</para> |
119 | ||
120 | <para>While running, containers invoked with <command>systemd-nspawn</command> are registered with the | |
121 | <citerefentry><refentrytitle>systemd-machined</refentrytitle><manvolnum>8</manvolnum></citerefentry> service that | |
122 | keeps track of running containers, and provides programming interfaces to interact with them.</para> | |
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123 | </refsect1> |
124 | ||
125 | <refsect1> | |
126 | <title>Options</title> | |
127 | ||
128 | <para>If option <option>-b</option> is specified, the arguments | |
3f2d1365 | 129 | are used as arguments for the init program. Otherwise, |
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130 | <replaceable>COMMAND</replaceable> specifies the program to launch |
131 | in the container, and the remaining arguments are used as | |
b09c0bba | 132 | arguments for this program. If <option>--boot</option> is not used and |
ff9b60f3 | 133 | no arguments are specified, a shell is launched in the |
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134 | container.</para> |
135 | ||
136 | <para>The following options are understood:</para> | |
137 | ||
138 | <variablelist> | |
139 | <varlistentry> | |
140 | <term><option>-D</option></term> | |
141 | <term><option>--directory=</option></term> | |
142 | ||
143 | <listitem><para>Directory to use as file system root for the | |
144 | container.</para> | |
145 | ||
146 | <para>If neither <option>--directory=</option>, nor | |
147 | <option>--image=</option> is specified the directory is | |
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148 | determined by searching for a directory named the same as the |
149 | machine name specified with <option>--machine=</option>. See | |
150 | <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry> | |
151 | section "Files and Directories" for the precise search path.</para> | |
152 | ||
153 | <para>If neither <option>--directory=</option>, | |
154 | <option>--image=</option>, nor <option>--machine=</option> | |
155 | are specified, the current directory will | |
156 | be used. May not be specified together with | |
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157 | <option>--image=</option>.</para></listitem> |
158 | </varlistentry> | |
159 | ||
160 | <varlistentry> | |
161 | <term><option>--template=</option></term> | |
162 | ||
17cbb288 LP |
163 | <listitem><para>Directory or <literal>btrfs</literal> subvolume to use as template for the container's root |
164 | directory. If this is specified and the container's root directory (as configured by | |
165 | <option>--directory=</option>) does not yet exist it is created as <literal>btrfs</literal> snapshot (if | |
166 | supported) or plain directory (otherwise) and populated from this template tree. Ideally, the specified | |
167 | template path refers to the root of a <literal>btrfs</literal> subvolume, in which case a simple copy-on-write | |
168 | snapshot is taken, and populating the root directory is instant. If the specified template path does not refer | |
169 | to the root of a <literal>btrfs</literal> subvolume (or not even to a <literal>btrfs</literal> file system at | |
170 | all), the tree is copied (though possibly in a copy-on-write scheme — if the file system supports that), which | |
171 | can be substantially more time-consuming. May not be specified together with <option>--image=</option> or | |
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172 | <option>--ephemeral</option>.</para> |
173 | ||
174 | <para>Note that this switch leaves host name, machine ID and | |
175 | all other settings that could identify the instance | |
176 | unmodified.</para></listitem> | |
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177 | </varlistentry> |
178 | ||
179 | <varlistentry> | |
180 | <term><option>-x</option></term> | |
181 | <term><option>--ephemeral</option></term> | |
182 | ||
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183 | <listitem><para>If specified, the container is run with a temporary snapshot of its file system that is removed |
184 | immediately when the container terminates. May not be specified together with | |
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185 | <option>--template=</option>.</para> |
186 | <para>Note that this switch leaves host name, machine ID and | |
187 | all other settings that could identify the instance | |
188 | unmodified.</para></listitem> | |
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189 | </varlistentry> |
190 | ||
191 | <varlistentry> | |
192 | <term><option>-i</option></term> | |
193 | <term><option>--image=</option></term> | |
194 | ||
195 | <listitem><para>Disk image to mount the root directory for the | |
196 | container from. Takes a path to a regular file or to a block | |
197 | device node. The file or block device must contain | |
198 | either:</para> | |
199 | ||
200 | <itemizedlist> | |
201 | <listitem><para>An MBR partition table with a single | |
202 | partition of type 0x83 that is marked | |
203 | bootable.</para></listitem> | |
204 | ||
205 | <listitem><para>A GUID partition table (GPT) with a single | |
206 | partition of type | |
207 | 0fc63daf-8483-4772-8e79-3d69d8477de4.</para></listitem> | |
208 | ||
209 | <listitem><para>A GUID partition table (GPT) with a marked | |
210 | root partition which is mounted as the root directory of the | |
211 | container. Optionally, GPT images may contain a home and/or | |
212 | a server data partition which are mounted to the appropriate | |
213 | places in the container. All these partitions must be | |
214 | identified by the partition types defined by the <ulink | |
28a0ad81 | 215 | url="https://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/">Discoverable |
798d3a52 | 216 | Partitions Specification</ulink>.</para></listitem> |
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217 | |
218 | <listitem><para>No partition table, and a single file system spanning the whole image.</para></listitem> | |
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219 | </itemizedlist> |
220 | ||
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221 | <para>On GPT images, if an EFI System Partition (ESP) is discovered, it is automatically mounted to |
222 | <filename>/efi</filename> (or <filename>/boot</filename> as fallback) in case a directory by this name exists | |
223 | and is empty.</para> | |
224 | ||
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225 | <para>Partitions encrypted with LUKS are automatically decrypted. Also, on GPT images dm-verity data integrity |
226 | hash partitions are set up if the root hash for them is specified using the <option>--root-hash=</option> | |
227 | option.</para> | |
228 | ||
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229 | <para>Any other partitions, such as foreign partitions or swap partitions are not mounted. May not be specified |
230 | together with <option>--directory=</option>, <option>--template=</option>.</para></listitem> | |
798d3a52 | 231 | </varlistentry> |
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232 | |
233 | <varlistentry> | |
234 | <term><option>--root-hash=</option></term> | |
235 | ||
236 | <listitem><para>Takes a data integrity (dm-verity) root hash specified in hexadecimal. This option enables data | |
237 | integrity checks using dm-verity, if the used image contains the appropriate integrity data (see above). The | |
ef3116b5 | 238 | specified hash must match the root hash of integrity data, and is usually at least 256 bits (and hence 64 |
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239 | formatted hexadecimal characters) long (in case of SHA256 for example). If this option is not specified, but |
240 | the image file carries the <literal>user.verity.roothash</literal> extended file attribute (see <citerefentry | |
241 | project='man-pages'><refentrytitle>xattr</refentrytitle><manvolnum>7</manvolnum></citerefentry>), then the root | |
242 | hash is read from it, also as formatted hexadecimal characters. If the extended file attribute is not found (or | |
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243 | is not supported by the underlying file system), but a file with the <filename>.roothash</filename> suffix is |
244 | found next to the image file, bearing otherwise the same name, the root hash is read from it and automatically | |
245 | used, also as formatted hexadecimal characters.</para></listitem> | |
58abb66f | 246 | </varlistentry> |
798d3a52 | 247 | |
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248 | <varlistentry> |
249 | <term><option>-a</option></term> | |
250 | <term><option>--as-pid2</option></term> | |
251 | ||
252 | <listitem><para>Invoke the shell or specified program as process ID (PID) 2 instead of PID 1 (init). By | |
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253 | default, if neither this option nor <option>--boot</option> is used, the selected program is run as the process |
254 | with PID 1, a mode only suitable for programs that are aware of the special semantics that the process with | |
255 | PID 1 has on UNIX. For example, it needs to reap all processes reparented to it, and should implement | |
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256 | <command>sysvinit</command> compatible signal handling (specifically: it needs to reboot on SIGINT, reexecute |
257 | on SIGTERM, reload configuration on SIGHUP, and so on). With <option>--as-pid2</option> a minimal stub init | |
3f2d1365 | 258 | process is run as PID 1 and the selected program is executed as PID 2 (and hence does not need to implement any |
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259 | special semantics). The stub init process will reap processes as necessary and react appropriately to |
260 | signals. It is recommended to use this mode to invoke arbitrary commands in containers, unless they have been | |
261 | modified to run correctly as PID 1. Or in other words: this switch should be used for pretty much all commands, | |
262 | except when the command refers to an init or shell implementation, as these are generally capable of running | |
a6b5216c | 263 | correctly as PID 1. This option may not be combined with <option>--boot</option>.</para> |
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264 | </listitem> |
265 | </varlistentry> | |
266 | ||
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267 | <varlistentry> |
268 | <term><option>-b</option></term> | |
269 | <term><option>--boot</option></term> | |
270 | ||
3f2d1365 | 271 | <listitem><para>Automatically search for an init program and invoke it as PID 1, instead of a shell or a user |
7732f92b | 272 | supplied program. If this option is used, arguments specified on the command line are used as arguments for the |
3f2d1365 | 273 | init program. This option may not be combined with <option>--as-pid2</option>.</para> |
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274 | |
275 | <para>The following table explains the different modes of invocation and relationship to | |
276 | <option>--as-pid2</option> (see above):</para> | |
277 | ||
278 | <table> | |
279 | <title>Invocation Mode</title> | |
280 | <tgroup cols='2' align='left' colsep='1' rowsep='1'> | |
281 | <colspec colname="switch" /> | |
282 | <colspec colname="explanation" /> | |
283 | <thead> | |
284 | <row> | |
285 | <entry>Switch</entry> | |
286 | <entry>Explanation</entry> | |
287 | </row> | |
288 | </thead> | |
289 | <tbody> | |
290 | <row> | |
291 | <entry>Neither <option>--as-pid2</option> nor <option>--boot</option> specified</entry> | |
4447e799 | 292 | <entry>The passed parameters are interpreted as the command line, which is executed as PID 1 in the container.</entry> |
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293 | </row> |
294 | ||
295 | <row> | |
296 | <entry><option>--as-pid2</option> specified</entry> | |
4447e799 | 297 | <entry>The passed parameters are interpreted as the command line, which is executed as PID 2 in the container. A stub init process is run as PID 1.</entry> |
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298 | </row> |
299 | ||
300 | <row> | |
301 | <entry><option>--boot</option> specified</entry> | |
3f2d1365 | 302 | <entry>An init program is automatically searched for and run as PID 1 in the container. The passed parameters are used as invocation parameters for this process.</entry> |
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303 | </row> |
304 | ||
305 | </tbody> | |
306 | </tgroup> | |
307 | </table> | |
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308 | |
309 | <para>Note that <option>--boot</option> is the default mode of operation if the | |
310 | <filename>systemd-nspawn@.service</filename> template unit file is used.</para> | |
7732f92b | 311 | </listitem> |
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312 | </varlistentry> |
313 | ||
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314 | <varlistentry> |
315 | <term><option>--chdir=</option></term> | |
316 | ||
317 | <listitem><para>Change to the specified working directory before invoking the process in the container. Expects | |
318 | an absolute path in the container's file system namespace.</para></listitem> | |
319 | </varlistentry> | |
320 | ||
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321 | <varlistentry> |
322 | <term><option>--pivot-root=</option></term> | |
323 | ||
324 | <listitem><para>Pivot the specified directory to <filename>/</filename> inside the container, and either unmount the | |
325 | container's old root, or pivot it to another specified directory. Takes one of: a path argument — in which case the | |
326 | specified path will be pivoted to <filename>/</filename> and the old root will be unmounted; or a colon-separated pair | |
327 | of new root path and pivot destination for the old root. The new root path will be pivoted to <filename>/</filename>, | |
328 | and the old <filename>/</filename> will be pivoted to the other directory. Both paths must be absolute, and are resolved | |
329 | in the container's file system namespace.</para> | |
330 | ||
331 | <para>This is for containers which have several bootable directories in them; for example, several | |
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332 | <ulink url="https://ostree.readthedocs.io/en/latest/">OSTree</ulink> deployments. It emulates the behavior of |
333 | the boot loader and initial RAM disk which normally select which directory to mount as the root and start the | |
334 | container's PID 1 in.</para></listitem> | |
b53ede69 PW |
335 | </varlistentry> |
336 | ||
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337 | <varlistentry> |
338 | <term><option>-u</option></term> | |
339 | <term><option>--user=</option></term> | |
340 | ||
341 | <listitem><para>After transitioning into the container, change | |
342 | to the specified user-defined in the container's user | |
343 | database. Like all other systemd-nspawn features, this is not | |
344 | a security feature and provides protection against accidental | |
345 | destructive operations only.</para></listitem> | |
346 | </varlistentry> | |
347 | ||
348 | <varlistentry> | |
349 | <term><option>-M</option></term> | |
350 | <term><option>--machine=</option></term> | |
351 | ||
352 | <listitem><para>Sets the machine name for this container. This | |
353 | name may be used to identify this container during its runtime | |
354 | (for example in tools like | |
355 | <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry> | |
356 | and similar), and is used to initialize the container's | |
357 | hostname (which the container can choose to override, | |
358 | however). If not specified, the last component of the root | |
359 | directory path of the container is used, possibly suffixed | |
360 | with a random identifier in case <option>--ephemeral</option> | |
361 | mode is selected. If the root directory selected is the host's | |
362 | root directory the host's hostname is used as default | |
363 | instead.</para></listitem> | |
364 | </varlistentry> | |
365 | ||
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366 | <varlistentry> |
367 | <term><option>--hostname=</option></term> | |
368 | ||
369 | <listitem><para>Controls the hostname to set within the container, if different from the machine name. Expects | |
370 | a valid hostname as argument. If this option is used, the kernel hostname of the container will be set to this | |
371 | value, otherwise it will be initialized to the machine name as controlled by the <option>--machine=</option> | |
372 | option described above. The machine name is used for various aspect of identification of the container from the | |
373 | outside, the kernel hostname configurable with this option is useful for the container to identify itself from | |
374 | the inside. It is usually a good idea to keep both forms of identification synchronized, in order to avoid | |
375 | confusion. It is hence recommended to avoid usage of this option, and use <option>--machine=</option> | |
376 | exclusively. Note that regardless whether the container's hostname is initialized from the name set with | |
377 | <option>--hostname=</option> or the one set with <option>--machine=</option>, the container can later override | |
378 | its kernel hostname freely on its own as well.</para> | |
379 | </listitem> | |
380 | </varlistentry> | |
381 | ||
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382 | <varlistentry> |
383 | <term><option>--uuid=</option></term> | |
384 | ||
385 | <listitem><para>Set the specified UUID for the container. The | |
386 | init system will initialize | |
387 | <filename>/etc/machine-id</filename> from this if this file is | |
e01ff70a MS |
388 | not set yet. Note that this option takes effect only if |
389 | <filename>/etc/machine-id</filename> in the container is | |
390 | unpopulated.</para></listitem> | |
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391 | </varlistentry> |
392 | ||
393 | <varlistentry> | |
4deb5503 | 394 | <term><option>-S</option></term> |
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395 | <term><option>--slice=</option></term> |
396 | ||
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397 | <listitem><para>Make the container part of the specified slice, instead of the default |
398 | <filename>machine.slice</filename>. This applies only if the machine is run in its own scope unit, i.e. if | |
399 | <option>--keep-unit</option> isn't used.</para> | |
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400 | </listitem> |
401 | </varlistentry> | |
402 | ||
403 | <varlistentry> | |
404 | <term><option>--property=</option></term> | |
405 | ||
cd2dfc6f LP |
406 | <listitem><para>Set a unit property on the scope unit to register for the machine. This applies only if the |
407 | machine is run in its own scope unit, i.e. if <option>--keep-unit</option> isn't used. Takes unit property | |
408 | assignments in the same format as <command>systemctl set-property</command>. This is useful to set memory | |
409 | limits and similar for container.</para> | |
798d3a52 ZJS |
410 | </listitem> |
411 | </varlistentry> | |
412 | ||
03cfe0d5 LP |
413 | <varlistentry> |
414 | <term><option>--private-users=</option></term> | |
415 | ||
d2e5535f LP |
416 | <listitem><para>Controls user namespacing. If enabled, the container will run with its own private set of UNIX |
417 | user and group ids (UIDs and GIDs). This involves mapping the private UIDs/GIDs used in the container (starting | |
418 | with the container's root user 0 and up) to a range of UIDs/GIDs on the host that are not used for other | |
419 | purposes (usually in the range beyond the host's UID/GID 65536). The parameter may be specified as follows:</para> | |
420 | ||
421 | <orderedlist> | |
2dd67817 | 422 | <listitem><para>If one or two colon-separated numbers are specified, user namespacing is turned on. The first |
ae209204 ZJS |
423 | parameter specifies the first host UID/GID to assign to the container, the second parameter specifies the |
424 | number of host UIDs/GIDs to assign to the container. If the second parameter is omitted, 65536 UIDs/GIDs are | |
425 | assigned.</para></listitem> | |
426 | ||
427 | <listitem><para>If the parameter is omitted, or true, user namespacing is turned on. The UID/GID range to | |
428 | use is determined automatically from the file ownership of the root directory of the container's directory | |
429 | tree. To use this option, make sure to prepare the directory tree in advance, and ensure that all files and | |
430 | directories in it are owned by UIDs/GIDs in the range you'd like to use. Also, make sure that used file ACLs | |
431 | exclusively reference UIDs/GIDs in the appropriate range. If this mode is used the number of UIDs/GIDs | |
432 | assigned to the container for use is 65536, and the UID/GID of the root directory must be a multiple of | |
433 | 65536.</para></listitem> | |
434 | ||
435 | <listitem><para>If the parameter is false, user namespacing is turned off. This is the default.</para> | |
436 | </listitem> | |
437 | ||
438 | <listitem><para>The special value <literal>pick</literal> turns on user namespacing. In this case the UID/GID | |
439 | range is automatically chosen. As first step, the file owner of the root directory of the container's | |
440 | directory tree is read, and it is checked that it is currently not used by the system otherwise (in | |
441 | particular, that no other container is using it). If this check is successful, the UID/GID range determined | |
2dd67817 | 442 | this way is used, similar to the behavior if "yes" is specified. If the check is not successful (and thus |
ae209204 ZJS |
443 | the UID/GID range indicated in the root directory's file owner is already used elsewhere) a new – currently |
444 | unused – UID/GID range of 65536 UIDs/GIDs is randomly chosen between the host UID/GIDs of 524288 and | |
445 | 1878982656, always starting at a multiple of 65536. This setting implies | |
446 | <option>--private-users-chown</option> (see below), which has the effect that the files and directories in | |
447 | the container's directory tree will be owned by the appropriate users of the range picked. Using this option | |
2dd67817 | 448 | makes user namespace behavior fully automatic. Note that the first invocation of a previously unused |
ae209204 ZJS |
449 | container image might result in picking a new UID/GID range for it, and thus in the (possibly expensive) file |
450 | ownership adjustment operation. However, subsequent invocations of the container will be cheap (unless of | |
451 | course the picked UID/GID range is assigned to a different use by then).</para></listitem> | |
d2e5535f LP |
452 | </orderedlist> |
453 | ||
454 | <para>It is recommended to assign at least 65536 UIDs/GIDs to each container, so that the usable UID/GID range in the | |
455 | container covers 16 bit. For best security, do not assign overlapping UID/GID ranges to multiple containers. It is | |
456 | hence a good idea to use the upper 16 bit of the host 32-bit UIDs/GIDs as container identifier, while the lower 16 | |
2dd67817 | 457 | bit encode the container UID/GID used. This is in fact the behavior enforced by the |
d2e5535f LP |
458 | <option>--private-users=pick</option> option.</para> |
459 | ||
460 | <para>When user namespaces are used, the GID range assigned to each container is always chosen identical to the | |
461 | UID range.</para> | |
462 | ||
463 | <para>In most cases, using <option>--private-users=pick</option> is the recommended option as it enhances | |
464 | container security massively and operates fully automatically in most cases.</para> | |
465 | ||
466 | <para>Note that the picked UID/GID range is not written to <filename>/etc/passwd</filename> or | |
467 | <filename>/etc/group</filename>. In fact, the allocation of the range is not stored persistently anywhere, | |
aa10469e LP |
468 | except in the file ownership of the files and directories of the container.</para> |
469 | ||
470 | <para>Note that when user namespacing is used file ownership on disk reflects this, and all of the container's | |
471 | files and directories are owned by the container's effective user and group IDs. This means that copying files | |
472 | from and to the container image requires correction of the numeric UID/GID values, according to the UID/GID | |
473 | shift applied.</para></listitem> | |
03cfe0d5 LP |
474 | </varlistentry> |
475 | ||
d2e5535f LP |
476 | <varlistentry> |
477 | <term><option>--private-users-chown</option></term> | |
478 | ||
479 | <listitem><para>If specified, all files and directories in the container's directory tree will adjusted so that | |
480 | they are owned to the appropriate UIDs/GIDs selected for the container (see above). This operation is | |
481 | potentially expensive, as it involves descending and iterating through the full directory tree of the | |
482 | container. Besides actual file ownership, file ACLs are adjusted as well.</para> | |
483 | ||
484 | <para>This option is implied if <option>--private-users=pick</option> is used. This option has no effect if | |
485 | user namespacing is not used.</para></listitem> | |
486 | </varlistentry> | |
03cfe0d5 | 487 | |
6265bde2 ZJS |
488 | <varlistentry> |
489 | <term><option>-U</option></term> | |
490 | ||
491 | <listitem><para>If the kernel supports the user namespaces feature, equivalent to | |
492 | <option>--private-users=pick --private-users-chown</option>, otherwise equivalent to | |
493 | <option>--private-users=no</option>.</para> | |
494 | ||
495 | <para>Note that <option>-U</option> is the default if the | |
496 | <filename>systemd-nspawn@.service</filename> template unit file is used.</para> | |
497 | ||
498 | <para>Note: it is possible to undo the effect of <option>--private-users-chown</option> (or | |
499 | <option>-U</option>) on the file system by redoing the operation with the first UID of 0:</para> | |
500 | ||
501 | <programlisting>systemd-nspawn … --private-users=0 --private-users-chown</programlisting> | |
502 | </listitem> | |
503 | </varlistentry> | |
504 | ||
798d3a52 ZJS |
505 | <varlistentry> |
506 | <term><option>--private-network</option></term> | |
507 | ||
508 | <listitem><para>Disconnect networking of the container from | |
509 | the host. This makes all network interfaces unavailable in the | |
510 | container, with the exception of the loopback device and those | |
511 | specified with <option>--network-interface=</option> and | |
512 | configured with <option>--network-veth</option>. If this | |
513 | option is specified, the CAP_NET_ADMIN capability will be | |
514 | added to the set of capabilities the container retains. The | |
bc96c63c ZJS |
515 | latter may be disabled by using <option>--drop-capability=</option>. |
516 | If this option is not specified (or implied by one of the options | |
517 | listed below), the container will have full access to the host network. | |
518 | </para></listitem> | |
798d3a52 ZJS |
519 | </varlistentry> |
520 | ||
d7bea6b6 DP |
521 | <varlistentry> |
522 | <term><option>--network-namespace-path=</option></term> | |
523 | ||
524 | <listitem><para>Takes the path to a file representing a kernel | |
525 | network namespace that the container shall run in. The specified path | |
526 | should refer to a (possibly bind-mounted) network namespace file, as | |
527 | exposed by the kernel below <filename>/proc/$PID/ns/net</filename>. | |
528 | This makes the container enter the given network namespace. One of the | |
529 | typical use cases is to give a network namespace under | |
530 | <filename>/run/netns</filename> created by <citerefentry | |
531 | project='man-pages'><refentrytitle>ip-netns</refentrytitle><manvolnum>8</manvolnum></citerefentry>, | |
532 | for example, <option>--network-namespace-path=/run/netns/foo</option>. | |
533 | Note that this option cannot be used together with other | |
534 | network-related options, such as <option>--private-network</option> | |
535 | or <option>--network-interface=</option>.</para></listitem> | |
536 | </varlistentry> | |
537 | ||
798d3a52 ZJS |
538 | <varlistentry> |
539 | <term><option>--network-interface=</option></term> | |
540 | ||
541 | <listitem><para>Assign the specified network interface to the | |
542 | container. This will remove the specified interface from the | |
543 | calling namespace and place it in the container. When the | |
544 | container terminates, it is moved back to the host namespace. | |
545 | Note that <option>--network-interface=</option> implies | |
546 | <option>--private-network</option>. This option may be used | |
547 | more than once to add multiple network interfaces to the | |
548 | container.</para></listitem> | |
549 | </varlistentry> | |
550 | ||
551 | <varlistentry> | |
552 | <term><option>--network-macvlan=</option></term> | |
553 | ||
554 | <listitem><para>Create a <literal>macvlan</literal> interface | |
555 | of the specified Ethernet network interface and add it to the | |
556 | container. A <literal>macvlan</literal> interface is a virtual | |
557 | interface that adds a second MAC address to an existing | |
558 | physical Ethernet link. The interface in the container will be | |
559 | named after the interface on the host, prefixed with | |
560 | <literal>mv-</literal>. Note that | |
561 | <option>--network-macvlan=</option> implies | |
562 | <option>--private-network</option>. This option may be used | |
563 | more than once to add multiple network interfaces to the | |
564 | container.</para></listitem> | |
565 | </varlistentry> | |
566 | ||
567 | <varlistentry> | |
568 | <term><option>--network-ipvlan=</option></term> | |
569 | ||
570 | <listitem><para>Create an <literal>ipvlan</literal> interface | |
571 | of the specified Ethernet network interface and add it to the | |
572 | container. An <literal>ipvlan</literal> interface is a virtual | |
573 | interface, similar to a <literal>macvlan</literal> interface, | |
574 | which uses the same MAC address as the underlying interface. | |
575 | The interface in the container will be named after the | |
576 | interface on the host, prefixed with <literal>iv-</literal>. | |
577 | Note that <option>--network-ipvlan=</option> implies | |
578 | <option>--private-network</option>. This option may be used | |
579 | more than once to add multiple network interfaces to the | |
580 | container.</para></listitem> | |
581 | </varlistentry> | |
582 | ||
583 | <varlistentry> | |
584 | <term><option>-n</option></term> | |
585 | <term><option>--network-veth</option></term> | |
586 | ||
5e7423ff LP |
587 | <listitem><para>Create a virtual Ethernet link (<literal>veth</literal>) between host and container. The host |
588 | side of the Ethernet link will be available as a network interface named after the container's name (as | |
589 | specified with <option>--machine=</option>), prefixed with <literal>ve-</literal>. The container side of the | |
590 | Ethernet link will be named <literal>host0</literal>. The <option>--network-veth</option> option implies | |
591 | <option>--private-network</option>.</para> | |
592 | ||
593 | <para>Note that | |
594 | <citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> | |
595 | includes by default a network file <filename>/usr/lib/systemd/network/80-container-ve.network</filename> | |
596 | matching the host-side interfaces created this way, which contains settings to enable automatic address | |
597 | provisioning on the created virtual link via DHCP, as well as automatic IP routing onto the host's external | |
598 | network interfaces. It also contains <filename>/usr/lib/systemd/network/80-container-host0.network</filename> | |
599 | matching the container-side interface created this way, containing settings to enable client side address | |
600 | assignment via DHCP. In case <filename>systemd-networkd</filename> is running on both the host and inside the | |
601 | container, automatic IP communication from the container to the host is thus available, with further | |
602 | connectivity to the external network.</para> | |
b09c0bba LP |
603 | |
604 | <para>Note that <option>--network-veth</option> is the default if the | |
605 | <filename>systemd-nspawn@.service</filename> template unit file is used.</para> | |
5e7423ff | 606 | </listitem> |
798d3a52 ZJS |
607 | </varlistentry> |
608 | ||
f6d6bad1 LP |
609 | <varlistentry> |
610 | <term><option>--network-veth-extra=</option></term> | |
611 | ||
612 | <listitem><para>Adds an additional virtual Ethernet link | |
613 | between host and container. Takes a colon-separated pair of | |
614 | host interface name and container interface name. The latter | |
615 | may be omitted in which case the container and host sides will | |
616 | be assigned the same name. This switch is independent of | |
ccddd104 | 617 | <option>--network-veth</option>, and — in contrast — may be |
f6d6bad1 LP |
618 | used multiple times, and allows configuration of the network |
619 | interface names. Note that <option>--network-bridge=</option> | |
620 | has no effect on interfaces created with | |
621 | <option>--network-veth-extra=</option>.</para></listitem> | |
622 | </varlistentry> | |
623 | ||
798d3a52 ZJS |
624 | <varlistentry> |
625 | <term><option>--network-bridge=</option></term> | |
626 | ||
5e7423ff LP |
627 | <listitem><para>Adds the host side of the Ethernet link created with <option>--network-veth</option> to the |
628 | specified Ethernet bridge interface. Expects a valid network interface name of a bridge device as | |
629 | argument. Note that <option>--network-bridge=</option> implies <option>--network-veth</option>. If this option | |
630 | is used, the host side of the Ethernet link will use the <literal>vb-</literal> prefix instead of | |
798d3a52 ZJS |
631 | <literal>ve-</literal>.</para></listitem> |
632 | </varlistentry> | |
633 | ||
938d2579 LP |
634 | <varlistentry> |
635 | <term><option>--network-zone=</option></term> | |
636 | ||
637 | <listitem><para>Creates a virtual Ethernet link (<literal>veth</literal>) to the container and adds it to an | |
638 | automatically managed Ethernet bridge interface. The bridge interface is named after the passed argument, | |
639 | prefixed with <literal>vz-</literal>. The bridge interface is automatically created when the first container | |
640 | configured for its name is started, and is automatically removed when the last container configured for its | |
641 | name exits. Hence, each bridge interface configured this way exists only as long as there's at least one | |
642 | container referencing it running. This option is very similar to <option>--network-bridge=</option>, besides | |
643 | this automatic creation/removal of the bridge device.</para> | |
644 | ||
645 | <para>This setting makes it easy to place multiple related containers on a common, virtual Ethernet-based | |
646 | broadcast domain, here called a "zone". Each container may only be part of one zone, but each zone may contain | |
647 | any number of containers. Each zone is referenced by its name. Names may be chosen freely (as long as they form | |
648 | valid network interface names when prefixed with <literal>vz-</literal>), and it is sufficient to pass the same | |
cf917c27 | 649 | name to the <option>--network-zone=</option> switch of the various concurrently running containers to join |
938d2579 LP |
650 | them in one zone.</para> |
651 | ||
652 | <para>Note that | |
653 | <citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> | |
654 | includes by default a network file <filename>/usr/lib/systemd/network/80-container-vz.network</filename> | |
655 | matching the bridge interfaces created this way, which contains settings to enable automatic address | |
656 | provisioning on the created virtual network via DHCP, as well as automatic IP routing onto the host's external | |
657 | network interfaces. Using <option>--network-zone=</option> is hence in most cases fully automatic and | |
658 | sufficient to connect multiple local containers in a joined broadcast domain to the host, with further | |
659 | connectivity to the external network.</para> | |
660 | </listitem> | |
661 | </varlistentry> | |
662 | ||
798d3a52 ZJS |
663 | <varlistentry> |
664 | <term><option>-p</option></term> | |
665 | <term><option>--port=</option></term> | |
666 | ||
667 | <listitem><para>If private networking is enabled, maps an IP | |
668 | port on the host onto an IP port on the container. Takes a | |
669 | protocol specifier (either <literal>tcp</literal> or | |
670 | <literal>udp</literal>), separated by a colon from a host port | |
671 | number in the range 1 to 65535, separated by a colon from a | |
672 | container port number in the range from 1 to 65535. The | |
673 | protocol specifier and its separating colon may be omitted, in | |
674 | which case <literal>tcp</literal> is assumed. The container | |
7c918141 | 675 | port number and its colon may be omitted, in which case the |
798d3a52 | 676 | same port as the host port is implied. This option is only |
a8eaaee7 | 677 | supported if private networking is used, such as with |
938d2579 | 678 | <option>--network-veth</option>, <option>--network-zone=</option> |
798d3a52 ZJS |
679 | <option>--network-bridge=</option>.</para></listitem> |
680 | </varlistentry> | |
681 | ||
682 | <varlistentry> | |
683 | <term><option>-Z</option></term> | |
684 | <term><option>--selinux-context=</option></term> | |
685 | ||
686 | <listitem><para>Sets the SELinux security context to be used | |
687 | to label processes in the container.</para> | |
688 | </listitem> | |
689 | </varlistentry> | |
690 | ||
691 | <varlistentry> | |
692 | <term><option>-L</option></term> | |
693 | <term><option>--selinux-apifs-context=</option></term> | |
694 | ||
695 | <listitem><para>Sets the SELinux security context to be used | |
696 | to label files in the virtual API file systems in the | |
697 | container.</para> | |
698 | </listitem> | |
699 | </varlistentry> | |
700 | ||
701 | <varlistentry> | |
702 | <term><option>--capability=</option></term> | |
703 | ||
a30504ed AJ |
704 | <listitem><para>List one or more additional capabilities to grant the container. |
705 | Takes a comma-separated list of capability names, see | |
798d3a52 | 706 | <citerefentry project='man-pages'><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry> |
a30504ed AJ |
707 | for more information. Note that the following capabilities will be granted in any way: |
708 | CAP_AUDIT_CONTROL, CAP_AUDIT_WRITE, CAP_CHOWN, CAP_DAC_OVERRIDE, CAP_DAC_READ_SEARCH, | |
709 | CAP_FOWNER, CAP_FSETID, CAP_IPC_OWNER, CAP_KILL, CAP_LEASE, CAP_LINUX_IMMUTABLE, | |
710 | CAP_MKNOD, CAP_NET_BIND_SERVICE, CAP_NET_BROADCAST, CAP_NET_RAW, CAP_SETFCAP, | |
711 | CAP_SETGID, CAP_SETPCAP, CAP_SETUID, CAP_SYS_ADMIN, CAP_SYS_BOOT, CAP_SYS_CHROOT, | |
712 | CAP_SYS_NICE, CAP_SYS_PTRACE, CAP_SYS_RESOURCE, CAP_SYS_TTY_CONFIG. Also CAP_NET_ADMIN | |
713 | is retained if <option>--private-network</option> is specified. If the special value | |
714 | <literal>all</literal> is passed, all capabilities are retained.</para></listitem> | |
798d3a52 ZJS |
715 | </varlistentry> |
716 | ||
717 | <varlistentry> | |
718 | <term><option>--drop-capability=</option></term> | |
719 | ||
720 | <listitem><para>Specify one or more additional capabilities to | |
721 | drop for the container. This allows running the container with | |
722 | fewer capabilities than the default (see | |
723 | above).</para></listitem> | |
724 | </varlistentry> | |
725 | ||
66edd963 LP |
726 | <varlistentry> |
727 | <term><option>--no-new-privileges=</option></term> | |
728 | ||
729 | <listitem><para>Takes a boolean argument. Specifies the value of the <constant>PR_SET_NO_NEW_PRIVS</constant> | |
730 | flag for the container payload. Defaults to off. When turned on the payload code of the container cannot | |
731 | acquire new privileges, i.e. the "setuid" file bit as well as file system capabilities will not have an effect | |
732 | anymore. See <citerefentry | |
733 | project='man-pages'><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry> for details | |
734 | about this flag. </para></listitem> | |
735 | </varlistentry> | |
736 | ||
960e4569 LP |
737 | <varlistentry> |
738 | <term><option>--system-call-filter=</option></term> | |
739 | ||
740 | <listitem><para>Alter the system call filter applied to containers. Takes a space-separated list of system call | |
741 | names or group names (the latter prefixed with <literal>@</literal>, as listed by the | |
c7fc3c4c LP |
742 | <command>syscall-filter</command> command of |
743 | <citerefentry><refentrytitle>systemd-analyze</refentrytitle><manvolnum>1</manvolnum></citerefentry>). Passed | |
960e4569 LP |
744 | system calls will be permitted. The list may optionally be prefixed by <literal>~</literal>, in which case all |
745 | listed system calls are prohibited. If this command line option is used multiple times the configured lists are | |
746 | combined. If both a positive and a negative list (that is one system call list without and one with the | |
96bedbe2 LP |
747 | <literal>~</literal> prefix) are configured, the negative list takes precedence over the positive list. Note |
748 | that <command>systemd-nspawn</command> always implements a system call whitelist (as opposed to a blacklist), | |
749 | and this command line option hence adds or removes entries from the default whitelist, depending on the | |
960e4569 LP |
750 | <literal>~</literal> prefix. Note that the applied system call filter is also altered implicitly if additional |
751 | capabilities are passed using the <command>--capabilities=</command>.</para></listitem> | |
752 | </varlistentry> | |
753 | ||
bf428efb LP |
754 | <varlistentry> |
755 | <term><option>--rlimit=</option></term> | |
756 | ||
757 | <listitem><para>Sets the specified POSIX resource limit for the container payload. Expects an assignment of the | |
758 | form | |
759 | <literal><replaceable>LIMIT</replaceable>=<replaceable>SOFT</replaceable>:<replaceable>HARD</replaceable></literal> | |
760 | or <literal><replaceable>LIMIT</replaceable>=<replaceable>VALUE</replaceable></literal>, where | |
761 | <replaceable>LIMIT</replaceable> should refer to a resource limit type, such as | |
762 | <constant>RLIMIT_NOFILE</constant> or <constant>RLIMIT_NICE</constant>. The <replaceable>SOFT</replaceable> and | |
763 | <replaceable>HARD</replaceable> fields should refer to the numeric soft and hard resource limit values. If the | |
1b2ad5d9 | 764 | second form is used, <replaceable>VALUE</replaceable> may specify a value that is used both as soft and hard |
bf428efb LP |
765 | limit. In place of a numeric value the special string <literal>infinity</literal> may be used to turn off |
766 | resource limiting for the specific type of resource. This command line option may be used multiple times to | |
1b2ad5d9 | 767 | control limits on multiple limit types. If used multiple times for the same limit type, the last use |
bf428efb LP |
768 | wins. For details about resource limits see <citerefentry |
769 | project='man-pages'><refentrytitle>setrlimit</refentrytitle><manvolnum>2</manvolnum></citerefentry>. By default | |
770 | resource limits for the container's init process (PID 1) are set to the same values the Linux kernel originally | |
771 | passed to the host init system. Note that some resource limits are enforced on resources counted per user, in | |
772 | particular <constant>RLIMIT_NPROC</constant>. This means that unless user namespacing is deployed | |
773 | (i.e. <option>--private-users=</option> is used, see above), any limits set will be applied to the resource | |
774 | usage of the same user on all local containers as well as the host. This means particular care needs to be | |
775 | taken with these limits as they might be triggered by possibly less trusted code. Example: | |
776 | <literal>--rlimit=RLIMIT_NOFILE=8192:16384</literal>.</para></listitem> | |
777 | </varlistentry> | |
778 | ||
81f345df LP |
779 | <varlistentry> |
780 | <term><option>--oom-score-adjust=</option></term> | |
781 | ||
782 | <listitem><para>Changes the OOM ("Out Of Memory") score adjustment value for the container payload. This controls | |
783 | <filename>/proc/self/oom_score_adj</filename> which influences the preference with which this container is | |
784 | terminated when memory becomes scarce. For details see <citerefentry | |
785 | project='man-pages'><refentrytitle>proc</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Takes an | |
786 | integer in the range -1000…1000.</para></listitem> | |
787 | </varlistentry> | |
788 | ||
d107bb7d LP |
789 | <varlistentry> |
790 | <term><option>--cpu-affinity=</option></term> | |
791 | ||
792 | <listitem><para>Controls the CPU affinity of the container payload. Takes a comma separated list of CPU numbers | |
793 | or number ranges (the latter's start and end value separated by dashes). See <citerefentry | |
794 | project='man-pages'><refentrytitle>sched_setaffinity</refentrytitle><manvolnum>2</manvolnum></citerefentry> for | |
795 | details.</para></listitem> | |
796 | </varlistentry> | |
797 | ||
c6c8f6e2 LP |
798 | <varlistentry> |
799 | <term><option>--kill-signal=</option></term> | |
800 | ||
1752d69a LP |
801 | <listitem><para>Specify the process signal to send to the container's PID 1 when nspawn itself receives |
802 | <constant>SIGTERM</constant>, in order to trigger an orderly shutdown of the container. Defaults to | |
803 | <constant>SIGRTMIN+3</constant> if <option>--boot</option> is used (on systemd-compatible init systems | |
804 | <constant>SIGRTMIN+3</constant> triggers an orderly shutdown). If <option>--boot</option> is not used and this | |
805 | option is not specified the container's processes are terminated abrubtly via <constant>SIGKILL</constant>. For | |
806 | a list of valid signals, see <citerefentry | |
807 | project='man-pages'><refentrytitle>signal</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para></listitem> | |
c6c8f6e2 LP |
808 | </varlistentry> |
809 | ||
798d3a52 ZJS |
810 | <varlistentry> |
811 | <term><option>--link-journal=</option></term> | |
812 | ||
813 | <listitem><para>Control whether the container's journal shall | |
814 | be made visible to the host system. If enabled, allows viewing | |
815 | the container's journal files from the host (but not vice | |
816 | versa). Takes one of <literal>no</literal>, | |
817 | <literal>host</literal>, <literal>try-host</literal>, | |
818 | <literal>guest</literal>, <literal>try-guest</literal>, | |
819 | <literal>auto</literal>. If <literal>no</literal>, the journal | |
820 | is not linked. If <literal>host</literal>, the journal files | |
821 | are stored on the host file system (beneath | |
822 | <filename>/var/log/journal/<replaceable>machine-id</replaceable></filename>) | |
823 | and the subdirectory is bind-mounted into the container at the | |
824 | same location. If <literal>guest</literal>, the journal files | |
825 | are stored on the guest file system (beneath | |
826 | <filename>/var/log/journal/<replaceable>machine-id</replaceable></filename>) | |
827 | and the subdirectory is symlinked into the host at the same | |
828 | location. <literal>try-host</literal> and | |
829 | <literal>try-guest</literal> do the same but do not fail if | |
2dd67817 | 830 | the host does not have persistent journaling enabled. If |
798d3a52 ZJS |
831 | <literal>auto</literal> (the default), and the right |
832 | subdirectory of <filename>/var/log/journal</filename> exists, | |
833 | it will be bind mounted into the container. If the | |
834 | subdirectory does not exist, no linking is performed. | |
835 | Effectively, booting a container once with | |
836 | <literal>guest</literal> or <literal>host</literal> will link | |
837 | the journal persistently if further on the default of | |
b09c0bba LP |
838 | <literal>auto</literal> is used.</para> |
839 | ||
840 | <para>Note that <option>--link-journal=try-guest</option> is the default if the | |
841 | <filename>systemd-nspawn@.service</filename> template unit file is used.</para></listitem> | |
798d3a52 ZJS |
842 | </varlistentry> |
843 | ||
844 | <varlistentry> | |
845 | <term><option>-j</option></term> | |
846 | ||
847 | <listitem><para>Equivalent to | |
848 | <option>--link-journal=try-guest</option>.</para></listitem> | |
849 | </varlistentry> | |
850 | ||
09d423e9 LP |
851 | <varlistentry> |
852 | <term><option>--resolv-conf=</option></term> | |
853 | ||
854 | <listitem><para>Configures how <filename>/etc/resolv.conf</filename> inside of the container (i.e. DNS | |
855 | configuration synchronization from host to container) shall be handled. Takes one of <literal>off</literal>, | |
856 | <literal>copy-host</literal>, <literal>copy-static</literal>, <literal>bind-host</literal>, | |
857 | <literal>bind-static</literal>, <literal>delete</literal> or <literal>auto</literal>. If set to | |
858 | <literal>off</literal> the <filename>/etc/resolv.conf</filename> file in the container is left as it is | |
859 | included in the image, and neither modified nor bind mounted over. If set to <literal>copy-host</literal>, the | |
860 | <filename>/etc/resolv.conf</filename> file from the host is copied into the container. Similar, if | |
861 | <literal>bind-host</literal> is used, the file is bind mounted from the host into the container. If set to | |
862 | <literal>copy-static</literal> the static <filename>resolv.conf</filename> file supplied with | |
863 | <citerefentry><refentrytitle>systemd-resolved.service</refentrytitle><manvolnum>8</manvolnum></citerefentry> is | |
864 | copied into the container, and correspondingly <literal>bind-static</literal> bind mounts it there. If set to | |
865 | <literal>delete</literal> the <filename>/etc/resolv.conf</filename> file in the container is deleted if it | |
866 | exists. Finally, if set to <literal>auto</literal> the file is left as it is if private networking is turned on | |
867 | (see <option>--private-network</option>). Otherwise, if <filename>systemd-resolved.service</filename> is | |
868 | connectible its static <filename>resolv.conf</filename> file is used, and if not the host's | |
869 | <filename>/etc/resolv.conf</filename> file is used. In the latter cases the file is copied if the image is | |
870 | writable, and bind mounted otherwise. It's recommended to use <literal>copy</literal> if the container shall be | |
871 | able to make changes to the DNS configuration on its own, deviating from the host's settings. Otherwise | |
872 | <literal>bind</literal> is preferable, as it means direct changes to <filename>/etc/resolv.conf</filename> in | |
873 | the container are not allowed, as it is a read-only bind mount (but note that if the container has enough | |
874 | privileges, it might simply go ahead and unmount the bind mount anyway). Note that both if the file is bind | |
875 | mounted and if it is copied no further propagation of configuration is generally done after the one-time early | |
876 | initialization (this is because the file is usually updated through copying and renaming). Defaults to | |
877 | <literal>auto</literal>.</para></listitem> | |
878 | </varlistentry> | |
879 | ||
1688841f LP |
880 | <varlistentry> |
881 | <term><option>--timezone=</option></term> | |
882 | ||
883 | <listitem><para>Configures how <filename>/etc/localtime</filename> inside of the container (i.e. local timezone | |
884 | synchronization from host to container) shall be handled. Takes one of <literal>off</literal>, | |
885 | <literal>copy</literal>, <literal>bind</literal>, <literal>symlink</literal>, <literal>delete</literal> or | |
886 | <literal>auto</literal>. If set to <literal>off</literal> the <filename>/etc/localtime</filename> file in the | |
887 | container is left as it is included in the image, and neither modified nor bind mounted over. If set to | |
888 | <literal>copy</literal> the <filename>/etc/localtime</filename> file of the host is copied into the | |
889 | container. Similar, if <literal>bind</literal> is used, it is bind mounted from the host into the container. If | |
890 | set to <literal>symlink</literal> a symlink from <filename>/etc/localtime</filename> in the container is | |
891 | created pointing to the matching the timezone file of the container that matches the timezone setting on the | |
892 | host. If set to <literal>delete</literal> the file in the container is deleted, should it exist. If set to | |
893 | <literal>auto</literal> and the <filename>/etc/localtime</filename> file of the host is a symlink, then | |
894 | <literal>symlink</literal> mode is used, and <literal>copy</literal> otherwise, except if the image is | |
895 | read-only in which case <literal>bind</literal> is used instead. Defaults to | |
896 | <literal>auto</literal>.</para></listitem> | |
897 | </varlistentry> | |
898 | ||
798d3a52 ZJS |
899 | <varlistentry> |
900 | <term><option>--read-only</option></term> | |
901 | ||
902 | <listitem><para>Mount the root file system read-only for the | |
903 | container.</para></listitem> | |
904 | </varlistentry> | |
905 | ||
906 | <varlistentry> | |
907 | <term><option>--bind=</option></term> | |
908 | <term><option>--bind-ro=</option></term> | |
909 | ||
86c0dd4a | 910 | <listitem><para>Bind mount a file or directory from the host into the container. Takes one of: a path |
c7a4890c LP |
911 | argument — in which case the specified path will be mounted from the host to the same path in the container, or |
912 | a colon-separated pair of paths — in which case the first specified path is the source in the host, and the | |
913 | second path is the destination in the container, or a colon-separated triple of source path, destination path | |
86c0dd4a | 914 | and mount options. The source path may optionally be prefixed with a <literal>+</literal> character. If so, the |
c7a4890c LP |
915 | source path is taken relative to the image's root directory. This permits setting up bind mounts within the |
916 | container image. The source path may be specified as empty string, in which case a temporary directory below | |
917 | the host's <filename>/var/tmp</filename> directory is used. It is automatically removed when the container is | |
918 | shut down. Mount options are comma-separated and currently, only <option>rbind</option> and | |
919 | <option>norbind</option> are allowed, controlling whether to create a recursive or a regular bind | |
920 | mount. Defaults to "rbind". Backslash escapes are interpreted, so <literal>\:</literal> may be used to embed | |
921 | colons in either path. This option may be specified multiple times for creating multiple independent bind | |
994a6364 LP |
922 | mount points. The <option>--bind-ro=</option> option creates read-only bind mounts.</para> |
923 | ||
924 | <para>Note that when this option is used in combination with <option>--private-users</option>, the resulting | |
925 | mount points will be owned by the <constant>nobody</constant> user. That's because the mount and its files and | |
926 | directories continue to be owned by the relevant host users and groups, which do not exist in the container, | |
927 | and thus show up under the wildcard UID 65534 (nobody). If such bind mounts are created, it is recommended to | |
928 | make them read-only, using <option>--bind-ro=</option>.</para></listitem> | |
798d3a52 ZJS |
929 | </varlistentry> |
930 | ||
931 | <varlistentry> | |
932 | <term><option>--tmpfs=</option></term> | |
933 | ||
934 | <listitem><para>Mount a tmpfs file system into the container. | |
935 | Takes a single absolute path argument that specifies where to | |
936 | mount the tmpfs instance to (in which case the directory | |
937 | access mode will be chosen as 0755, owned by root/root), or | |
938 | optionally a colon-separated pair of path and mount option | |
b938cb90 | 939 | string that is used for mounting (in which case the kernel |
798d3a52 ZJS |
940 | default for access mode and owner will be chosen, unless |
941 | otherwise specified). This option is particularly useful for | |
942 | mounting directories such as <filename>/var</filename> as | |
943 | tmpfs, to allow state-less systems, in particular when | |
ffcd3e89 | 944 | combined with <option>--read-only</option>. |
b938cb90 | 945 | Backslash escapes are interpreted in the path, so |
ffcd3e89 RM |
946 | <literal>\:</literal> may be used to embed colons in the path. |
947 | </para></listitem> | |
798d3a52 ZJS |
948 | </varlistentry> |
949 | ||
5a8af538 LP |
950 | <varlistentry> |
951 | <term><option>--overlay=</option></term> | |
952 | <term><option>--overlay-ro=</option></term> | |
953 | ||
954 | <listitem><para>Combine multiple directory trees into one | |
955 | overlay file system and mount it into the container. Takes a | |
956 | list of colon-separated paths to the directory trees to | |
957 | combine and the destination mount point.</para> | |
958 | ||
2eadf91c RM |
959 | <para>Backslash escapes are interpreted in the paths, so |
960 | <literal>\:</literal> may be used to embed colons in the paths. | |
961 | </para> | |
962 | ||
5a8af538 LP |
963 | <para>If three or more paths are specified, then the last |
964 | specified path is the destination mount point in the | |
965 | container, all paths specified before refer to directory trees | |
966 | on the host and are combined in the specified order into one | |
967 | overlay file system. The left-most path is hence the lowest | |
968 | directory tree, the second-to-last path the highest directory | |
969 | tree in the stacking order. If <option>--overlay-ro=</option> | |
b938cb90 | 970 | is used instead of <option>--overlay=</option>, a read-only |
5a8af538 | 971 | overlay file system is created. If a writable overlay file |
b938cb90 | 972 | system is created, all changes made to it are written to the |
5a8af538 LP |
973 | highest directory tree in the stacking order, i.e. the |
974 | second-to-last specified.</para> | |
975 | ||
976 | <para>If only two paths are specified, then the second | |
977 | specified path is used both as the top-level directory tree in | |
978 | the stacking order as seen from the host, as well as the mount | |
979 | point for the overlay file system in the container. At least | |
980 | two paths have to be specified.</para> | |
981 | ||
86c0dd4a | 982 | <para>The source paths may optionally be prefixed with <literal>+</literal> character. If so they are taken |
c7a4890c LP |
983 | relative to the image's root directory. The uppermost source path may also be specified as empty string, in |
984 | which case a temporary directory below the host's <filename>/var/tmp</filename> is used. The directory is | |
985 | removed automatically when the container is shut down. This behaviour is useful in order to make read-only | |
986 | container directories writable while the container is running. For example, use the | |
987 | <literal>--overlay=+/var::/var</literal> option in order to automatically overlay a writable temporary | |
988 | directory on a read-only <filename>/var</filename> directory.</para> | |
86c0dd4a | 989 | |
5a8af538 LP |
990 | <para>For details about overlay file systems, see <ulink |
991 | url="https://www.kernel.org/doc/Documentation/filesystems/overlayfs.txt">overlayfs.txt</ulink>. Note | |
992 | that the semantics of overlay file systems are substantially | |
993 | different from normal file systems, in particular regarding | |
994 | reported device and inode information. Device and inode | |
995 | information may change for a file while it is being written | |
996 | to, and processes might see out-of-date versions of files at | |
997 | times. Note that this switch automatically derives the | |
998 | <literal>workdir=</literal> mount option for the overlay file | |
999 | system from the top-level directory tree, making it a sibling | |
1000 | of it. It is hence essential that the top-level directory tree | |
1001 | is not a mount point itself (since the working directory must | |
1002 | be on the same file system as the top-most directory | |
1003 | tree). Also note that the <literal>lowerdir=</literal> mount | |
1004 | option receives the paths to stack in the opposite order of | |
1005 | this switch.</para></listitem> | |
1006 | </varlistentry> | |
1007 | ||
798d3a52 | 1008 | <varlistentry> |
a5f1cb3b ZJS |
1009 | <term><option>-E <replaceable>NAME</replaceable>=<replaceable>VALUE</replaceable></option></term> |
1010 | <term><option>--setenv=<replaceable>NAME</replaceable>=<replaceable>VALUE</replaceable></option></term> | |
798d3a52 ZJS |
1011 | |
1012 | <listitem><para>Specifies an environment variable assignment | |
1013 | to pass to the init process in the container, in the format | |
1014 | <literal>NAME=VALUE</literal>. This may be used to override | |
1015 | the default variables or to set additional variables. This | |
1016 | parameter may be used more than once.</para></listitem> | |
1017 | </varlistentry> | |
1018 | ||
798d3a52 ZJS |
1019 | <varlistentry> |
1020 | <term><option>--register=</option></term> | |
1021 | ||
cd2dfc6f LP |
1022 | <listitem><para>Controls whether the container is registered with |
1023 | <citerefentry><refentrytitle>systemd-machined</refentrytitle><manvolnum>8</manvolnum></citerefentry>. Takes a | |
1024 | boolean argument, which defaults to <literal>yes</literal>. This option should be enabled when the container | |
1025 | runs a full Operating System (more specifically: a system and service manager as PID 1), and is useful to | |
1026 | ensure that the container is accessible via | |
1027 | <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry> and shown by | |
1028 | tools such as <citerefentry | |
1029 | project='man-pages'><refentrytitle>ps</refentrytitle><manvolnum>1</manvolnum></citerefentry>. If the container | |
1030 | does not run a service manager, it is recommended to set this option to | |
1031 | <literal>no</literal>.</para></listitem> | |
798d3a52 ZJS |
1032 | </varlistentry> |
1033 | ||
1034 | <varlistentry> | |
1035 | <term><option>--keep-unit</option></term> | |
1036 | ||
bb849957 LP |
1037 | <listitem><para>Instead of creating a transient scope unit to run the container in, simply use the service or |
1038 | scope unit <command>systemd-nspawn</command> has been invoked in. If <option>--register=yes</option> is set | |
1039 | this unit is registered with | |
1040 | <citerefentry><refentrytitle>systemd-machined</refentrytitle><manvolnum>8</manvolnum></citerefentry>. This | |
1041 | switch should be used if <command>systemd-nspawn</command> is invoked from within a service unit, and the | |
1042 | service unit's sole purpose is to run a single <command>systemd-nspawn</command> container. This option is not | |
1043 | available if run from a user session.</para> | |
cd2dfc6f | 1044 | <para>Note that passing <option>--keep-unit</option> disables the effect of <option>--slice=</option> and |
bb849957 LP |
1045 | <option>--property=</option>. Use <option>--keep-unit</option> and <option>--register=no</option> in |
1046 | combination to disable any kind of unit allocation or registration with | |
1047 | <command>systemd-machined</command>.</para></listitem> | |
798d3a52 ZJS |
1048 | </varlistentry> |
1049 | ||
1050 | <varlistentry> | |
1051 | <term><option>--personality=</option></term> | |
1052 | ||
1053 | <listitem><para>Control the architecture ("personality") | |
1054 | reported by | |
3ba3a79d | 1055 | <citerefentry project='man-pages'><refentrytitle>uname</refentrytitle><manvolnum>2</manvolnum></citerefentry> |
798d3a52 ZJS |
1056 | in the container. Currently, only <literal>x86</literal> and |
1057 | <literal>x86-64</literal> are supported. This is useful when | |
1058 | running a 32-bit container on a 64-bit host. If this setting | |
1059 | is not used, the personality reported in the container is the | |
1060 | same as the one reported on the host.</para></listitem> | |
1061 | </varlistentry> | |
1062 | ||
1063 | <varlistentry> | |
1064 | <term><option>-q</option></term> | |
1065 | <term><option>--quiet</option></term> | |
1066 | ||
1067 | <listitem><para>Turns off any status output by the tool | |
1068 | itself. When this switch is used, the only output from nspawn | |
1069 | will be the console output of the container OS | |
1070 | itself.</para></listitem> | |
1071 | </varlistentry> | |
1072 | ||
1073 | <varlistentry> | |
f757855e LP |
1074 | <term><option>--volatile</option></term> |
1075 | <term><option>--volatile=</option><replaceable>MODE</replaceable></term> | |
798d3a52 ZJS |
1076 | |
1077 | <listitem><para>Boots the container in volatile mode. When no | |
1078 | mode parameter is passed or when mode is specified as | |
b938cb90 | 1079 | <option>yes</option>, full volatile mode is enabled. This |
a8eaaee7 | 1080 | means the root directory is mounted as a mostly unpopulated |
798d3a52 | 1081 | <literal>tmpfs</literal> instance, and |
cd72d204 JE |
1082 | <filename>/usr</filename> from the OS tree is mounted into it |
1083 | in read-only mode (the system thus starts up with read-only OS | |
5164c3b4 ZJS |
1084 | image, but pristine state and configuration, any changes |
1085 | are lost on shutdown). When the mode parameter | |
b938cb90 | 1086 | is specified as <option>state</option>, the OS tree is |
798d3a52 | 1087 | mounted read-only, but <filename>/var</filename> is mounted as |
a8eaaee7 | 1088 | a <literal>tmpfs</literal> instance into it (the system thus |
798d3a52 | 1089 | starts up with read-only OS resources and configuration, but |
a8eaaee7 | 1090 | pristine state, and any changes to the latter are lost on |
798d3a52 | 1091 | shutdown). When the mode parameter is specified as |
b938cb90 | 1092 | <option>no</option> (the default), the whole OS tree is made |
798d3a52 ZJS |
1093 | available writable.</para> |
1094 | ||
91214a37 LP |
1095 | <para>This option provides similar functionality for containers as the <literal>systemd.volatile=</literal> |
1096 | kernel command line switch provides for host systems. See | |
1097 | <citerefentry><refentrytitle>kernel-command-line</refentrytitle><manvolnum>7</manvolnum></citerefentry> for | |
1098 | details.</para> | |
1099 | ||
1100 | <para>Note that enabling this setting will only work correctly with operating systems in the container that can | |
1101 | boot up with only <filename>/usr</filename> mounted, and are able to automatically populate | |
1102 | <filename>/var</filename>, and also <filename>/etc</filename> in case of | |
1103 | <literal>--volatile=yes</literal>.</para></listitem> | |
798d3a52 ZJS |
1104 | </varlistentry> |
1105 | ||
f757855e LP |
1106 | <varlistentry> |
1107 | <term><option>--settings=</option><replaceable>MODE</replaceable></term> | |
1108 | ||
1109 | <listitem><para>Controls whether | |
1110 | <command>systemd-nspawn</command> shall search for and use | |
1111 | additional per-container settings from | |
1112 | <filename>.nspawn</filename> files. Takes a boolean or the | |
1113 | special values <option>override</option> or | |
1114 | <option>trusted</option>.</para> | |
1115 | ||
b938cb90 | 1116 | <para>If enabled (the default), a settings file named after the |
f757855e LP |
1117 | machine (as specified with the <option>--machine=</option> |
1118 | setting, or derived from the directory or image file name) | |
1119 | with the suffix <filename>.nspawn</filename> is searched in | |
1120 | <filename>/etc/systemd/nspawn/</filename> and | |
1121 | <filename>/run/systemd/nspawn/</filename>. If it is found | |
1122 | there, its settings are read and used. If it is not found | |
b938cb90 | 1123 | there, it is subsequently searched in the same directory as the |
f757855e | 1124 | image file or in the immediate parent of the root directory of |
b938cb90 | 1125 | the container. In this case, if the file is found, its settings |
f757855e | 1126 | will be also read and used, but potentially unsafe settings |
b938cb90 | 1127 | are ignored. Note that in both these cases, settings on the |
4f76ef04 | 1128 | command line take precedence over the corresponding settings |
f757855e LP |
1129 | from loaded <filename>.nspawn</filename> files, if both are |
1130 | specified. Unsafe settings are considered all settings that | |
1131 | elevate the container's privileges or grant access to | |
1132 | additional resources such as files or directories of the | |
1133 | host. For details about the format and contents of | |
b938cb90 | 1134 | <filename>.nspawn</filename> files, consult |
f757855e LP |
1135 | <citerefentry><refentrytitle>systemd.nspawn</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para> |
1136 | ||
b938cb90 JE |
1137 | <para>If this option is set to <option>override</option>, the |
1138 | file is searched, read and used the same way, however, the order of | |
f757855e LP |
1139 | precedence is reversed: settings read from the |
1140 | <filename>.nspawn</filename> file will take precedence over | |
1141 | the corresponding command line options, if both are | |
1142 | specified.</para> | |
1143 | ||
b938cb90 | 1144 | <para>If this option is set to <option>trusted</option>, the |
f757855e | 1145 | file is searched, read and used the same way, but regardless |
a8eaaee7 | 1146 | of being found in <filename>/etc/systemd/nspawn/</filename>, |
f757855e LP |
1147 | <filename>/run/systemd/nspawn/</filename> or next to the image |
1148 | file or container root directory, all settings will take | |
b938cb90 | 1149 | effect, however, command line arguments still take precedence |
f757855e LP |
1150 | over corresponding settings.</para> |
1151 | ||
b938cb90 | 1152 | <para>If disabled, no <filename>.nspawn</filename> file is read |
f757855e LP |
1153 | and no settings except the ones on the command line are in |
1154 | effect.</para></listitem> | |
1155 | </varlistentry> | |
1156 | ||
9c1e04d0 | 1157 | <varlistentry> |
b09c0bba | 1158 | <term><option>--notify-ready=</option></term> |
9c1e04d0 AP |
1159 | |
1160 | <listitem><para>Configures support for notifications from the container's init process. | |
b09c0bba | 1161 | <option>--notify-ready=</option> takes a boolean (<option>no</option> and <option>yes</option>). |
9c1e04d0 AP |
1162 | With option <option>no</option> systemd-nspawn notifies systemd |
1163 | with a <literal>READY=1</literal> message when the init process is created. | |
1164 | With option <option>yes</option> systemd-nspawn waits for the | |
1165 | <literal>READY=1</literal> message from the init process in the container | |
1166 | before sending its own to systemd. For more details about notifications | |
1167 | see <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>).</para></listitem> | |
1168 | </varlistentry> | |
1169 | ||
798d3a52 ZJS |
1170 | <xi:include href="standard-options.xml" xpointer="help" /> |
1171 | <xi:include href="standard-options.xml" xpointer="version" /> | |
1172 | </variablelist> | |
1173 | ||
1174 | </refsect1> | |
1175 | ||
1176 | <refsect1> | |
1177 | <title>Examples</title> | |
1178 | ||
1179 | <example> | |
12c4ee0a ZJS |
1180 | <title>Download a |
1181 | <ulink url="https://getfedora.org">Fedora</ulink> image and start a shell in it</title> | |
798d3a52 | 1182 | |
3797fd0a | 1183 | <programlisting># machinectl pull-raw --verify=no \ |
7a8aa0ec ZJS |
1184 | https://download.fedoraproject.org/pub/fedora/linux/releases/&fedora_latest_version;/Cloud/x86_64/images/Fedora-Cloud-Base-&fedora_latest_version;-&fedora_cloud_release;.x86_64.raw.xz |
1185 | # systemd-nspawn -M Fedora-Cloud-Base-&fedora_latest_version;-&fedora_cloud_release;.x86_64.raw</programlisting> | |
e0ea94c1 | 1186 | |
798d3a52 ZJS |
1187 | <para>This downloads an image using |
1188 | <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry> | |
1189 | and opens a shell in it.</para> | |
1190 | </example> | |
e0ea94c1 | 1191 | |
798d3a52 ZJS |
1192 | <example> |
1193 | <title>Build and boot a minimal Fedora distribution in a container</title> | |
8f7a3c14 | 1194 | |
7a8aa0ec | 1195 | <programlisting># dnf -y --releasever=&fedora_latest_version; --installroot=/var/lib/machines/f&fedora_latest_version; \ |
3797fd0a ZJS |
1196 | --disablerepo='*' --enablerepo=fedora --enablerepo=updates install \ |
1197 | systemd passwd dnf fedora-release vim-minimal | |
7a8aa0ec | 1198 | # systemd-nspawn -bD /var/lib/machines/f&fedora_latest_version;</programlisting> |
8f7a3c14 | 1199 | |
798d3a52 | 1200 | <para>This installs a minimal Fedora distribution into the |
7a8aa0ec | 1201 | directory <filename noindex='true'>/var/lib/machines/f&fedora_latest_version;</filename> |
55107232 ZJS |
1202 | and then boots an OS in a namespace container in it. Because the installation |
1203 | is located underneath the standard <filename>/var/lib/machines/</filename> | |
1204 | directory, it is also possible to start the machine using | |
7a8aa0ec | 1205 | <command>systemd-nspawn -M f&fedora_latest_version;</command>.</para> |
798d3a52 | 1206 | </example> |
8f7a3c14 | 1207 | |
798d3a52 ZJS |
1208 | <example> |
1209 | <title>Spawn a shell in a container of a minimal Debian unstable distribution</title> | |
8f7a3c14 | 1210 | |
7f8b3d1d | 1211 | <programlisting># debootstrap unstable ~/debian-tree/ |
25f5971b | 1212 | # systemd-nspawn -D ~/debian-tree/</programlisting> |
8f7a3c14 | 1213 | |
798d3a52 ZJS |
1214 | <para>This installs a minimal Debian unstable distribution into |
1215 | the directory <filename>~/debian-tree/</filename> and then | |
1216 | spawns a shell in a namespace container in it.</para> | |
12c4ee0a ZJS |
1217 | |
1218 | <para><command>debootstrap</command> supports | |
1219 | <ulink url="https://www.debian.org">Debian</ulink>, | |
1220 | <ulink url="https://www.ubuntu.com">Ubuntu</ulink>, | |
1221 | and <ulink url="https://www.tanglu.org">Tanglu</ulink> | |
1222 | out of the box, so the same command can be used to install any of those. For other | |
1223 | distributions from the Debian family, a mirror has to be specified, see | |
1224 | <citerefentry project='die-net'><refentrytitle>debootstrap</refentrytitle><manvolnum>8</manvolnum></citerefentry>. | |
1225 | </para> | |
798d3a52 | 1226 | </example> |
8f7a3c14 | 1227 | |
798d3a52 | 1228 | <example> |
12c4ee0a ZJS |
1229 | <title>Boot a minimal |
1230 | <ulink url="https://www.archlinux.org">Arch Linux</ulink> distribution in a container</title> | |
68562936 | 1231 | |
798d3a52 | 1232 | <programlisting># pacstrap -c -d ~/arch-tree/ base |
68562936 WG |
1233 | # systemd-nspawn -bD ~/arch-tree/</programlisting> |
1234 | ||
ff9b60f3 | 1235 | <para>This installs a minimal Arch Linux distribution into the |
798d3a52 ZJS |
1236 | directory <filename>~/arch-tree/</filename> and then boots an OS |
1237 | in a namespace container in it.</para> | |
1238 | </example> | |
68562936 | 1239 | |
f518ee04 | 1240 | <example> |
12c4ee0a ZJS |
1241 | <title>Install the |
1242 | <ulink url="https://software.opensuse.org/distributions/tumbleweed">OpenSUSE Tumbleweed</ulink> | |
1243 | rolling distribution</title> | |
f518ee04 ZJS |
1244 | |
1245 | <programlisting># zypper --root=/var/lib/machines/tumbleweed ar -c \ | |
1246 | https://download.opensuse.org/tumbleweed/repo/oss tumbleweed | |
1247 | # zypper --root=/var/lib/machines/tumbleweed refresh | |
1248 | # zypper --root=/var/lib/machines/tumbleweed install --no-recommends \ | |
1249 | systemd shadow zypper openSUSE-release vim | |
1250 | # systemd-nspawn -M tumbleweed passwd root | |
1251 | # systemd-nspawn -M tumbleweed -b</programlisting> | |
1252 | </example> | |
1253 | ||
798d3a52 | 1254 | <example> |
17cbb288 | 1255 | <title>Boot into an ephemeral snapshot of the host system</title> |
f9f4dd51 | 1256 | |
798d3a52 | 1257 | <programlisting># systemd-nspawn -D / -xb</programlisting> |
f9f4dd51 | 1258 | |
17cbb288 LP |
1259 | <para>This runs a copy of the host system in a snapshot which is removed immediately when the container |
1260 | exits. All file system changes made during runtime will be lost on shutdown, hence.</para> | |
798d3a52 | 1261 | </example> |
f9f4dd51 | 1262 | |
798d3a52 ZJS |
1263 | <example> |
1264 | <title>Run a container with SELinux sandbox security contexts</title> | |
a8828ed9 | 1265 | |
798d3a52 | 1266 | <programlisting># chcon system_u:object_r:svirt_sandbox_file_t:s0:c0,c1 -R /srv/container |
3797fd0a ZJS |
1267 | # systemd-nspawn -L system_u:object_r:svirt_sandbox_file_t:s0:c0,c1 \ |
1268 | -Z system_u:system_r:svirt_lxc_net_t:s0:c0,c1 -D /srv/container /bin/sh</programlisting> | |
798d3a52 | 1269 | </example> |
b53ede69 PW |
1270 | |
1271 | <example> | |
1272 | <title>Run a container with an OSTree deployment</title> | |
1273 | ||
3797fd0a ZJS |
1274 | <programlisting># systemd-nspawn -b -i ~/image.raw \ |
1275 | --pivot-root=/ostree/deploy/$OS/deploy/$CHECKSUM:/sysroot \ | |
1276 | --bind=+/sysroot/ostree/deploy/$OS/var:/var</programlisting> | |
b53ede69 | 1277 | </example> |
798d3a52 ZJS |
1278 | </refsect1> |
1279 | ||
1280 | <refsect1> | |
1281 | <title>Exit status</title> | |
1282 | ||
1283 | <para>The exit code of the program executed in the container is | |
1284 | returned.</para> | |
1285 | </refsect1> | |
1286 | ||
1287 | <refsect1> | |
1288 | <title>See Also</title> | |
1289 | <para> | |
1290 | <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, | |
f757855e | 1291 | <citerefentry><refentrytitle>systemd.nspawn</refentrytitle><manvolnum>5</manvolnum></citerefentry>, |
798d3a52 ZJS |
1292 | <citerefentry project='man-pages'><refentrytitle>chroot</refentrytitle><manvolnum>1</manvolnum></citerefentry>, |
1293 | <citerefentry project='mankier'><refentrytitle>dnf</refentrytitle><manvolnum>8</manvolnum></citerefentry>, | |
798d3a52 ZJS |
1294 | <citerefentry project='die-net'><refentrytitle>debootstrap</refentrytitle><manvolnum>8</manvolnum></citerefentry>, |
1295 | <citerefentry project='archlinux'><refentrytitle>pacman</refentrytitle><manvolnum>8</manvolnum></citerefentry>, | |
f518ee04 | 1296 | <citerefentry project='mankier'><refentrytitle>zypper</refentrytitle><manvolnum>8</manvolnum></citerefentry>, |
798d3a52 ZJS |
1297 | <citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>, |
1298 | <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, | |
3ba3a79d | 1299 | <citerefentry project='man-pages'><refentrytitle>btrfs</refentrytitle><manvolnum>8</manvolnum></citerefentry> |
798d3a52 ZJS |
1300 | </para> |
1301 | </refsect1> | |
8f7a3c14 LP |
1302 | |
1303 | </refentry> |