diff --git a/man/journal-upload.conf.xml b/man/journal-upload.conf.xml
index 9d486d9801..cd3335452a 100644
--- a/man/journal-upload.conf.xml
+++ b/man/journal-upload.conf.xml
@@ -68,7 +68,8 @@
         <listitem><para>The URL to upload the journal entries to. See the description
         of <varname>--url=</varname> option in
         <citerefentry><refentrytitle>systemd-journal-upload</refentrytitle><manvolnum>8</manvolnum></citerefentry>
-        for the description of possible values.</para></listitem>
+        for the description of possible values. There is no default value, so either this
+        option or the command-line option must be always present to make an upload.</para></listitem>
       </varlistentry>
 
       <varlistentry>
diff --git a/man/systemd-journal-upload.service.xml b/man/systemd-journal-upload.service.xml
index 141e595400..f923e53d29 100644
--- a/man/systemd-journal-upload.service.xml
+++ b/man/systemd-journal-upload.service.xml
@@ -61,6 +61,12 @@
     Unless limited by one of the options specified below, all journal entries accessible to the user
     the program is running as will be uploaded, and then the program will wait and send new entries
     as they become available.</para>
+
+    <para><filename>systemd-journal-upload.service</filename> is a system service that uses
+    <command>systemd-journal-upload</command> to upload journal entries to a server. It uses the
+    configuration in
+    <citerefentry><refentrytitle>journal-upload.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
+    At least the <varname>URL=</varname> option must be specified.</para>
   </refsect1>
 
   <refsect1>