diff --git a/bin/rndc/rndc.c b/bin/rndc/rndc.c
index 9fce52850e..2d63602732 100644
--- a/bin/rndc/rndc.c
+++ b/bin/rndc/rndc.c
@@ -101,7 +101,7 @@ command is one of the following:\n\
   delzone [-clean] zone [class [view]]\n\
 		Removes zone from given view.\n\
   dnstap -reopen\n\
-		Close and re-open the DNSTAP output file.\n\
+		Close, truncate and re-open the DNSTAP output file.\n\
   dnstap -roll count\n\
 		Close, rename and re-open the DNSTAP output file(s).\n\
   dumpdb [-all|-cache|-zones|-adb|-bad|-fail] [view ...]\n\
diff --git a/bin/rndc/rndc.docbook b/bin/rndc/rndc.docbook
index dcd228db27..f719a22486 100644
--- a/bin/rndc/rndc.docbook
+++ b/bin/rndc/rndc.docbook
@@ -308,7 +308,8 @@
 	  <para>
 	    Close and re-open DNSTAP output files.
 	    <command>rndc dnstap -reopen</command> allows the output
-	    file to be renamed externally, then re-opened.
+	    file to be renamed externally, so
+	    that <command>named</command> can truncate and re-open it.
 	    <command>rndc dnstap -roll</command> causes the output file
 	    to be rolled automatically, similar to log files; the most
 	    recent output file has ".0" appended to its name; the
diff --git a/bin/tools/dnstap-read.docbook b/bin/tools/dnstap-read.docbook
index c0765da399..bbb43d9578 100644
--- a/bin/tools/dnstap-read.docbook
+++ b/bin/tools/dnstap-read.docbook
@@ -101,7 +101,7 @@
         <refentrytitle>named</refentrytitle><manvolnum>8</manvolnum>
       </citerefentry>,
       <citerefentry>
-        <refentrytitle>nsupdate</refentrytitle><manvolnum>8</manvolnum>
+        <refentrytitle>rndc</refentrytitle><manvolnum>8</manvolnum>
       </citerefentry>,
       <citetitle>BIND 9 Administrator Reference Manual</citetitle>.
     </para>