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man: add DOI for refereed article on Forward Secure Sealing to journald.conf(5)
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1 <?xml version='1.0'?> <!--*-nxml-*-->
2 <?xml-stylesheet type="text/xsl" href="http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl"?>
3 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
4         "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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9   Copyright 2010 Lennart Poettering
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24
25 <refentry id="systemd.swap">
26         <refentryinfo>
27                 <title>systemd.swap</title>
28                 <productname>systemd</productname>
29
30                 <authorgroup>
31                         <author>
32                                 <contrib>Developer</contrib>
33                                 <firstname>Lennart</firstname>
34                                 <surname>Poettering</surname>
35                                 <email>lennart@poettering.net</email>
36                         </author>
37                 </authorgroup>
38         </refentryinfo>
39
40         <refmeta>
41                 <refentrytitle>systemd.swap</refentrytitle>
42                 <manvolnum>5</manvolnum>
43         </refmeta>
44
45         <refnamediv>
46                 <refname>systemd.swap</refname>
47                 <refpurpose>Swap unit configuration</refpurpose>
48         </refnamediv>
49
50         <refsynopsisdiv>
51                 <para><filename><replaceable>swap</replaceable>.swap</filename></para>
52         </refsynopsisdiv>
53
54         <refsect1>
55                 <title>Description</title>
56
57                 <para>A unit configuration file whose name ends in
58                 <literal>.swap</literal> encodes information about a
59                 swap device or file for memory paging controlled and
60                 supervised by systemd.</para>
61
62                 <para>This man page lists the configuration options
63                 specific to this unit type. See
64                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
65                 for the common options of all unit configuration
66                 files. The common configuration items are configured
67                 in the generic [Unit] and [Install] sections. The swap
68                 specific configuration options are configured in the
69                 [Swap] section.</para>
70
71                 <para>Additional options are listed in
72                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
73                 which define the execution environment the
74                 <citerefentry><refentrytitle>swapon</refentrytitle><manvolnum>8</manvolnum></citerefentry>
75                 binary is executed in, and in
76                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
77                 which define the way the processes are
78                 terminated, and in
79                 <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
80                 which configure resource control settings for the
81                 processes of the service.</para>
82
83                 <para>Swap units must be named after the devices
84                 or files they control. Example: the swap device
85                 <filename noindex='true'>/dev/sda5</filename> must be configured in a
86                 unit file <filename>dev-sda5.swap</filename>. For
87                 details about the escaping logic used to convert a
88                 file system path to a unit name see
89                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
90
91                 <para>All swap units automatically get the appropriate
92                 dependencies on the devices or on the mount points
93                 of the files they are activated from.</para>
94
95                 <para>Swap units with
96                 <varname>DefaultDependencies=</varname> enabled
97                 implicitly acquire a conflicting dependency to
98                 <filename>umount.target</filename> so that they are
99                 deactivated at shutdown.</para>
100         </refsect1>
101
102         <refsect1>
103                 <title><filename>fstab</filename></title>
104
105                 <para>Swap units may either be configured via unit
106                 files, or via <filename>/etc/fstab</filename> (see
107                 <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>
108                 for details). Swaps listed in
109                 <filename>/etc/fstab</filename> will be converted into
110                 native units dynamically at boot and when the
111                 configuration of the system manager is
112                 reloaded. See
113                 <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>
114                 for details about the conversion.</para>
115
116                 <para>If a swap device or file is configured in both
117                 <filename>/etc/fstab</filename> and a unit file, the
118                 configuration in the latter takes precedence.</para>
119
120                 <para>Unless the <option>noauto</option> option is set
121                 for them all swap units configured in
122                 <filename>/etc/fstab</filename> are also added as
123                 requirements to <filename>swap.target</filename>, so
124                 that they are waited for and activated during
125                 boot.</para>
126         </refsect1>
127
128         <refsect1>
129                 <title>Options</title>
130
131                 <para>Swap files must include a [Swap] section, which
132                 carries information about the swap device it
133                 supervises. A number of options that may be used in
134                 this section are shared with other unit types. These
135                 options are documented in
136                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
137                 and
138                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The
139                 options specific to the [Swap] section of swap units
140                 are the following:</para>
141
142                 <variablelist class='unit-directives'>
143
144                         <varlistentry>
145                                 <term><varname>What=</varname></term>
146                                 <listitem><para>Takes an absolute path
147                                 of a device node or file to use for
148                                 paging. See
149                                 <citerefentry><refentrytitle>swapon</refentrytitle><manvolnum>8</manvolnum></citerefentry>
150                                 for details. If this refers to a
151                                 device node, a dependency on the
152                                 respective device unit is
153                                 automatically created. (See
154                                 <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>
155                                 for more information.) If this refers
156                                 to a file, a dependency on the
157                                 respective mount unit is automatically
158                                 created. (See
159                                 <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>
160                                 for more information.) This option is
161                                 mandatory.</para></listitem>
162                         </varlistentry>
163
164                         <varlistentry>
165                                 <term><varname>Priority=</varname></term>
166
167                                 <listitem><para>Swap priority to use
168                                 when activating the swap device or
169                                 file. This takes an integer. This
170                                 setting is optional.</para></listitem>
171                         </varlistentry>
172
173                         <varlistentry>
174                                 <term><varname>TimeoutSec=</varname></term>
175                                 <listitem><para>Configures the time to
176                                 wait for the swapon command to
177                                 finish. If a command does not exit
178                                 within the configured time, the swap
179                                 will be considered failed and be shut
180                                 down again. All commands still running
181                                 will be terminated forcibly via
182                                 <constant>SIGTERM</constant>, and after another delay of
183                                 this time with <constant>SIGKILL</constant>. (See
184                                 <option>KillMode=</option> in
185                                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>.)
186                                 Takes a unit-less value in seconds, or
187                                 a time span value such as "5min
188                                 20s". Pass 0 to disable the timeout
189                                 logic. Defaults to <varname>TimeoutStartSec=</varname> from the
190                                 manager configuration file.</para></listitem>
191                         </varlistentry>
192                 </variablelist>
193
194                 <para>Check
195                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
196                 and
197                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
198                 for more settings.</para>
199         </refsect1>
200
201         <refsect1>
202                   <title>See Also</title>
203                   <para>
204                           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
205                           <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
206                           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
207                           <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
208                           <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
209                           <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
210                           <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
211                           <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
212                           <citerefentry><refentrytitle>swapon</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
213                           <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
214                           <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
215                   </para>
216         </refsect1>
217
218 </refentry>