diff --git a/bin/tests/system/dnstap/README b/bin/tests/system/dnstap/README
new file mode 100644
index 0000000000..f4cb38569a
--- /dev/null
+++ b/bin/tests/system/dnstap/README
@@ -0,0 +1,20 @@
+Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+
+See COPYRIGHT in the source root or http://isc.org/copyright.html for terms.
+
+The "large-answer.fstrm" file was generated by configuring a named instance
+compiled with --enable-dnstap and --enable-fixed-rrset with the following
+directives:
+
+    minimal-responses yes;
+    rrset-order { order fixed; };
+    dnstap { auth response; };
+    dnstap-identity none;
+    dnstap-output file "large-answer.fstrm";
+
+The captured RRset from the "example." zone was created using:
+
+    $GENERATE 1-48 @ IN A 127.0.0.$
+
+A server instance set up this way was then queried non-recursively (RD=0) for
+"example/A".
diff --git a/bin/tests/system/dnstap/large-answer.fstrm b/bin/tests/system/dnstap/large-answer.fstrm
new file mode 100644
index 0000000000..873b3159c0
Binary files /dev/null and b/bin/tests/system/dnstap/large-answer.fstrm differ
diff --git a/bin/tests/system/dnstap/tests.sh b/bin/tests/system/dnstap/tests.sh
index 1396995026..83877b102f 100644
--- a/bin/tests/system/dnstap/tests.sh
+++ b/bin/tests/system/dnstap/tests.sh
@@ -736,5 +736,14 @@ EOF
 	status=`expr $status + $ret`
 fi
 
+echo_i "checking large packet printing"
+ret=0
+# Expect one occurrence of "opcode: QUERY" below "reponse_message_data" and
+# another one below "response_message".
+lines=`$DNSTAPREAD -y large-answer.fstrm | grep -c "opcode: QUERY"`
+[ $lines -eq 2 ] || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
 echo_i "exit status: $status"
 [ $status -eq 0 ] || exit 1
diff --git a/bin/tools/dnstap-read.c b/bin/tools/dnstap-read.c
index 2548bf0fac..94fc49a01c 100644
--- a/bin/tools/dnstap-read.c
+++ b/bin/tools/dnstap-read.c
@@ -155,6 +155,7 @@ print_packet(dns_dtdata_t *dt, const dns_master_style_t *style) {
 
 			result = dns_message_totext(dt->msg, style, 0, b);
 			if (result == ISC_R_NOSPACE) {
+				isc_buffer_clear(b);
 				textlen *= 2;
 				continue;
 			} else if (result == ISC_R_SUCCESS) {
diff --git a/util/copyrights b/util/copyrights
index aa2f95cee5..835d7db1aa 100644
--- a/util/copyrights
+++ b/util/copyrights
@@ -558,7 +558,9 @@
 ./bin/tests/system/dnssec/signer/general/bogus-ksk.key	X	2018,2019
 ./bin/tests/system/dnssec/signer/general/bogus-zsk.key	X	2018,2019
 ./bin/tests/system/dnssec/tests.sh		SH	2000,2001,2002,2004,2005,2006,2007,2008,2009,2010,2011,2012,2013,2014,2015,2016,2017,2018,2019
+./bin/tests/system/dnstap/README		TXT.BRIEF	2019
 ./bin/tests/system/dnstap/clean.sh		SH	2015,2016,2017,2018,2019
+./bin/tests/system/dnstap/large-answer.fstrm	X	2019
 ./bin/tests/system/dnstap/setup.sh		SH	2018,2019
 ./bin/tests/system/dnstap/tests.sh		SH	2015,2016,2017,2018,2019
 ./bin/tests/system/dnstap/ydump.py		PYTHON	2016,2017,2018,2019