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[thirdparty/systemd.git] / man / systemd-journal-remote.xml

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"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">

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<refentry id="systemd-journal-remote" conditional='HAVE_MICROHTTPD'
          xmlns:xi="http://www.w3.org/2001/XInclude">

  <refentryinfo>
    <title>systemd-journal-remote</title>
    <productname>systemd</productname>

    <authorgroup>
      <author>
        <contrib>Developer</contrib>
        <firstname>Zbigniew</firstname>
        <surname>Jędrzejewski-Szmek</surname>
        <email>zbyszek@in.waw.pl</email>
      </author>
    </authorgroup>
  </refentryinfo>

  <refmeta>
    <refentrytitle>systemd-journal-remote</refentrytitle>
    <manvolnum>8</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>systemd-journal-remote</refname>
    <refpurpose>Receive journal messages over the network</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <cmdsynopsis>
      <command>systemd-journal-remote</command>
      <arg choice="opt" rep="repeat">OPTIONS</arg>
      <arg choice="opt" rep="norepeat">-o/--output=<replaceable>DIR</replaceable>|<replaceable>FILE</replaceable></arg>
      <arg choice="opt" rep="repeat">SOURCES</arg>
    </cmdsynopsis>
  </refsynopsisdiv>

  <refsect1>
    <title>Description</title>

    <para>
      <filename>systemd-journal-remote</filename> is a command to
      receive serialized journal events and store them to the journal.
      Input streams are in the
      <ulink url="https://www.freedesktop.org/wiki/Software/systemd/export">
        Journal Export Format
      </ulink>,
      i.e. like the output from
      <command>journalctl --output=export</command>. For transport over
      the network, this serialized stream is usually carried over an
      HTTPS connection.
    </para>
  </refsect1>

  <refsect1>
    <title>Sources</title>

    <para>
      Sources can be either "active"
      (<command>systemd-journal-remote</command> requests and pulls
      the data), or "passive"
      (<command>systemd-journal-remote</command> waits for a
      connection and then receives events pushed by the other side).
    </para>

    <para>
      <command>systemd-journal-remote</command> can read more than one
      event stream at a time. They will be interleaved in the output
      file. In case of "active" connections, each "source" is one
      stream, and in case of "passive" connections, each connection can
      result in a separate stream. Sockets can be configured in
      "accept" mode (i.e. only one connection), or "listen" mode (i.e.
      multiple connections, each resulting in a stream).
    </para>

    <para>
      When there are no more connections, and no more can be created
      (there are no listening sockets), then
      <command>systemd-journal-remote</command> will exit.
    </para>

    <para>Active sources can be specified in the following
    ways:</para>

    <variablelist>
      <varlistentry>
        <term><arg choice="opt" rep="repeat">SOURCES</arg></term>

        <listitem><para>When <option>-</option> is given as a
        positional argument, events will be read from standard input.
        Other positional arguments will be treated as filenames
        to open and read from.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--url=<replaceable>ADDRESS</replaceable></option></term>

        <listitem><para>With the
        <option>--url=<replaceable>ADDRESS</replaceable></option> option,
        events will be retrieved using HTTP from
        <replaceable>ADDRESS</replaceable>. This URL should refer to the
        root of a remote
        <citerefentry><refentrytitle>systemd-journal-gatewayd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
        instance, e.g. http://some.host:19531/ or
        https://some.host:19531/.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--getter='<replaceable>PROG</replaceable> <arg choice="opt" rep="repeat">OPTIONS</arg>'</option></term>

        <listitem><para>Program to invoke to retrieve data. The journal
        event stream must be generated on standard output.</para>

        <para>Examples:</para>

        <programlisting>--getter='curl "-HAccept: application/vnd.fdo.journal" https://some.host:19531/'</programlisting>

        <programlisting>--getter='wget --header="Accept: application/vnd.fdo.journal" -O- https://some.host:19531/'</programlisting>
        </listitem>
      </varlistentry>
    </variablelist>

    <para>Passive sources can be specified in the following
    ways:</para>

    <variablelist>
      <varlistentry>
        <term><option>--listen-raw=<replaceable>ADDRESS</replaceable></option></term>

        <listitem><para><replaceable>ADDRESS</replaceable> must be an
        address suitable for <option>ListenStream=</option> (cf.
        <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
        <command>systemd-journal-remote</command> will listen on this
        socket for connections. Each connection is expected to be a
        stream of journal events.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--listen-http=<replaceable>ADDRESS</replaceable></option></term>
        <term><option>--listen-https=<replaceable>ADDRESS</replaceable></option></term>

        <listitem><para><replaceable>ADDRESS</replaceable> must be
        either a negative integer, in which case it will be
        interpreted as the (negated) file descriptor number, or an
        address suitable for <option>ListenStream=</option> (c.f.
        <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
        In the first case, matching file descriptor must be inherited
        through
        <varname>$LISTEN_FDS</varname>/<varname>$LISTEN_PID</varname>.
        In the second case, an HTTP or HTTPS server will be spawned on
        this port, respectively for <option>--listen-http</option> and
        <option>--listen-https</option>. Currently, only POST requests
        to <filename>/upload</filename> with <literal>Content-Type:
        application/vnd.fdo.journal</literal> are supported.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><varname>$LISTEN_FDS</varname></term>

        <listitem><para><command>systemd-journal-remote</command>
        supports the
        <varname>$LISTEN_FDS</varname>/<varname>$LISTEN_PID</varname>
        protocol. Open sockets inherited through socket activation
        behave like those opened with <option>--listen-raw=</option>
        described above, unless they are specified as an argument in
        <option>--listen-http=-<replaceable>n</replaceable></option>
        or
        <option>--listen-https=-<replaceable>n</replaceable></option>
        above. In the latter case, an HTTP or HTTPS server will be
        spawned using this descriptor and connections must be made
        over the HTTP protocol.</para>
        </listitem>
      </varlistentry>

    </variablelist>
  </refsect1>

  <refsect1>
    <title>Sinks</title>

    <para>The location of the output journal can be specified
    with <option>-o</option> or <option>--output=</option>.
    </para>

    <variablelist>
      <varlistentry>
        <term><option>--output=<replaceable>FILE</replaceable></option></term>

        <listitem><para>Will write to this journal file. The filename
        must end with <filename>.journal</filename>. The file will be
        created if it does not exist. If necessary (journal file full,
        or corrupted), the file will be renamed following normal
        journald rules and a new journal file will be created in its
        stead.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--output=<replaceable>DIR</replaceable></option></term>

        <listitem><para>Will create journal files underneath directory
        <replaceable>DIR</replaceable>. The directory must exist. If
        necessary (journal files over size, or corrupted), journal
        files will be rotated following normal journald rules. Names
        of files underneath <replaceable>DIR</replaceable> will be
        generated using the rules described below.</para></listitem>
      </varlistentry>
    </variablelist>

    <para>If <option>--output=</option> is not used, the output
    directory <filename>/var/log/journal/remote/</filename> will be
    used.  In case the output file is not specified, journal files
    will be created underneath the selected directory. Files will be
    called
    <filename>remote-<replaceable>hostname</replaceable>.journal</filename>,
    where the <replaceable>hostname</replaceable> part is the
    escaped hostname of the source endpoint of the connection, or the
    numerical address if the hostname cannot be determined.</para>

    <para>In the case that "active" sources are given by the positional
    arguments or <option>--getter=</option> option, the output file name
    must always be given explicitly.</para>
  </refsect1>

  <refsect1>
    <title>Options</title>

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

    <variablelist>
      <varlistentry>
        <term><option>--split-mode</option></term>

        <listitem><para>One of <constant>none</constant> or
        <constant>host</constant>. For the first, only one output
        journal file is used. For the latter, a separate output file
        is used, based on the hostname of the other endpoint of a
        connection.</para>

        <para>In the case that "active" sources are given by the positional
        arguments or <option>--getter=</option> option, the output file name must
        always be given explicitly and only <constant>none</constant>
        is allowed.</para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--compress</option> [<replaceable>BOOL</replaceable>]</term>

        <listitem><para>If this is set to <literal>yes</literal> then compress
        the data in the journal using XZ. The default is <literal>yes</literal>.
        </para></listitem>
      </varlistentry>

      <varlistentry>
        <term><option>--seal</option> [<replaceable>BOOL</replaceable>]</term>

        <listitem><para>If this is set to <literal>yes</literal> then
        periodically sign the data in the journal using Forward Secure Sealing.
        The default is <literal>no</literal>.</para></listitem>
      </varlistentry>

      <xi:include href="standard-options.xml" xpointer="help" />
      <xi:include href="standard-options.xml" xpointer="version" />
    </variablelist>
  </refsect1>

  <refsect1>
    <title>Examples</title>
    <para>Copy local journal events to a different journal directory:
    <programlisting>
journalctl -o export | systemd-journal-remote -o /tmp/dir/foo.journal -
    </programlisting>
    </para>

    <para>Retrieve all available events from a remote
    <citerefentry><refentrytitle>systemd-journal-gatewayd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
    instance and store them in
    <filename>/var/log/journal/remote/remote-some.host.journal</filename>:
    <programlisting>
systemd-journal-remote --url http://some.host:19531/
    </programlisting>
    </para>

    <para>Retrieve current boot events and wait for new events from a remote
    <citerefentry><refentrytitle>systemd-journal-gatewayd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
    instance, and store them in
    <filename>/var/log/journal/remote/remote-some.host.journal</filename>:
    <programlisting>
systemd-journal-remote --url http://some.host:19531/entries?boot&amp;follow
    </programlisting>
    </para>
</refsect1>

  <refsect1>
    <title>See Also</title>
    <para>
      <citerefentry><refentrytitle>systemd-journal-upload</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
      <citerefentry><refentrytitle>systemd-journal-gatewayd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
      <citerefentry><refentrytitle>journal-remote.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>
    </para>
  </refsect1>
</refentry>