diff --git a/bin/tests/system/cacheclean/clean.sh b/bin/tests/system/cacheclean/clean.sh
index 4cd319179e..52505a32dc 100644
--- a/bin/tests/system/cacheclean/clean.sh
+++ b/bin/tests/system/cacheclean/clean.sh
@@ -15,6 +15,7 @@
 
 rm -f dig.out.ns2
 rm -f dig.out.expire
+rm -f rndc.out.*
 rm -f sed.out.*
 rm -f */named.memstats
 rm -f */named.run
diff --git a/bin/tests/system/cacheclean/tests.sh b/bin/tests/system/cacheclean/tests.sh
index fb9248ce2b..ed9707a511 100755
--- a/bin/tests/system/cacheclean/tests.sh
+++ b/bin/tests/system/cacheclean/tests.sh
@@ -57,13 +57,7 @@ EOF
 }
 
 dump_cache () {
-        $RNDC $RNDCOPTS dumpdb -cache _default
-        for i in 0 1 2 3 4 5 6 7 8 9
-        do
-                grep '^; Dump complete$' ns2/named_dump.db > /dev/null && break
-                sleep 1
-        done
-        mv ns2/named_dump.db ns2/named_dump.db.$n
+        rndc_dumpdb ns2 -cache _default
 }
 
 clear_cache () {
@@ -113,7 +107,7 @@ echo_i "reset and check that records are correctly cached initially ($n)"
 ret=0
 load_cache
 dump_cache
-nrecords=`filter_tree flushtest.example ns2/named_dump.db.$n | egrep '(TXT|ANY)' | wc -l`
+nrecords=`filter_tree flushtest.example ns2/named_dump.db.test$n | egrep '(TXT|ANY)' | wc -l`
 [ $nrecords -eq 18 ] || { ret=1; echo_i "found $nrecords records expected 18"; }
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
@@ -123,7 +117,7 @@ echo_i "check flushing of the full cache ($n)"
 ret=0
 clear_cache
 dump_cache
-nrecords=`filter_tree flushtest.example ns2/named_dump.db.$n | wc -l`
+nrecords=`filter_tree flushtest.example ns2/named_dump.db.test$n | wc -l`
 [ $nrecords -eq 0 ] || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
@@ -207,7 +201,7 @@ n=`expr $n + 1`
 echo_i "check the number of cached records remaining ($n)"
 ret=0
 dump_cache
-nrecords=`filter_tree flushtest.example ns2/named_dump.db.$n | grep -v '^;' | egrep '(TXT|ANY)' | wc -l`
+nrecords=`filter_tree flushtest.example ns2/named_dump.db.test$n | grep -v '^;' | egrep '(TXT|ANY)' | wc -l`
 [ $nrecords -eq 17 ] || { ret=1; echo_i "found $nrecords records expected 17"; }
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
@@ -225,7 +219,7 @@ n=`expr $n + 1`
 echo_i "check the number of cached records remaining ($n)"
 ret=0
 dump_cache
-nrecords=`filter_tree flushtest.example ns2/named_dump.db.$n | egrep '(TXT|ANY)' | wc -l`
+nrecords=`filter_tree flushtest.example ns2/named_dump.db.test$n | egrep '(TXT|ANY)' | wc -l`
 [ $nrecords -eq 1 ] || { ret=1; echo_i "found $nrecords records expected 1"; }
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
@@ -235,17 +229,17 @@ echo_i "check flushtree clears adb correctly ($n)"
 ret=0
 load_cache
 dump_cache
-mv ns2/named_dump.db.$n ns2/named_dump.db.$n.a
+mv ns2/named_dump.db.test$n ns2/named_dump.db.test$n.a
 sed -n '/plain success\/timeout/,/Unassociated entries/p' \
-	ns2/named_dump.db.$n.a > sed.out.$n.a
+	ns2/named_dump.db.test$n.a > sed.out.$n.a
 grep 'plain success/timeout' sed.out.$n.a > /dev/null 2>&1 || ret=1
 grep 'Unassociated entries' sed.out.$n.a > /dev/null 2>&1 || ret=1
 grep 'ns.flushtest.example' sed.out.$n.a > /dev/null 2>&1 || ret=1
 $RNDC $RNDCOPTS flushtree flushtest.example || ret=1
 dump_cache
-mv ns2/named_dump.db.$n ns2/named_dump.db.$n.b
+mv ns2/named_dump.db.test$n ns2/named_dump.db.test$n.b
 sed -n '/plain success\/timeout/,/Unassociated entries/p' \
-	ns2/named_dump.db.$n.b > sed.out.$n.b
+	ns2/named_dump.db.test$n.b > sed.out.$n.b
 grep 'plain success/timeout' sed.out.$n.b > /dev/null 2>&1 || ret=1
 grep 'Unassociated entries' sed.out.$n.b > /dev/null 2>&1 || ret=1
 grep 'ns.flushtest.example' sed.out.$n.b > /dev/null 2>&1 && ret=1
diff --git a/bin/tests/system/conf.sh.common b/bin/tests/system/conf.sh.common
index 921c349a57..613c0cd72b 100644
--- a/bin/tests/system/conf.sh.common
+++ b/bin/tests/system/conf.sh.common
@@ -343,6 +343,48 @@ rndc_reconfig() {
     done
 }
 
+# rndc_dumpdb: call "rndc dumpdb [...]" and wait until it completes
+#
+# The first argument is the name server instance to send the command to, in the
+# form of "nsX" (where "X" is the instance number), e.g. "ns5".  The remaining
+# arguments, if any, are appended to the rndc command line after "dumpdb".
+#
+# Control channel configuration for the name server instance to send the
+# command to must match the contents of bin/tests/system/common/rndc.conf.
+#
+# rndc output is stored in a file called rndc.out.test${n}; the "n" variable is
+# required to be set by the calling tests.sh script.
+#
+# Return 0 if the dump completes successfully; return 1 if rndc returns an exit
+# code other than 0 or if the "; Dump complete" string does not appear in the
+# dump within 10 seconds.
+rndc_dumpdb() {
+	__ret=0
+	__dump_complete=0
+	__server="${1}"
+	__ip="10.53.0.$(echo "${__server}" | tr -c -d "0-9")"
+
+	shift
+	${RNDC} -c ../common/rndc.conf -p "${CONTROLPORT}" -s "${__ip}" dumpdb "$@" > "rndc.out.test${n}" 2>&1 || __ret=1
+
+	for _ in 0 1 2 3 4 5 6 7 8 9
+	do
+		if grep '^; Dump complete$' "${__server}/named_dump.db" > /dev/null; then
+			mv "${__server}/named_dump.db" "${__server}/named_dump.db.test${n}"
+			__dump_complete=1
+			break
+		fi
+		sleep 1
+	done
+
+	if [ ${__dump_complete} -eq 0 ]; then
+		echo_i "timed out waiting for 'rndc dumpdb' to finish"
+		__ret=1
+	fi
+
+	return ${__ret}
+}
+
 # get_dig_xfer_stats: extract transfer statistics from dig output stored
 # in $1, converting them to a format used by some system tests.
 get_dig_xfer_stats() {
diff --git a/bin/tests/system/cookie/clean.sh b/bin/tests/system/cookie/clean.sh
index b5888d1f5b..3439fc64b2 100644
--- a/bin/tests/system/cookie/clean.sh
+++ b/bin/tests/system/cookie/clean.sh
@@ -9,7 +9,8 @@
 
 rm -f ns*/named.conf
 rm -f dig.out.*
-rm -f ns1/named_dump.db
+rm -f rndc.out.*
+rm -f ns1/named_dump.db*
 rm -f ns*/named.memstats
 rm -f ns*/named.run
 rm -f ns*/named.lock
diff --git a/bin/tests/system/cookie/tests.sh b/bin/tests/system/cookie/tests.sh
index f82bb00546..8e71103942 100755
--- a/bin/tests/system/cookie/tests.sh
+++ b/bin/tests/system/cookie/tests.sh
@@ -141,13 +141,8 @@ status=`expr $status + $ret`
 n=`expr $n + 1`
 echo_i "checking for COOKIE value in adb ($n)"
 ret=0
-$RNDCCMD 10.53.0.1 dumpdb
-for i in 1 2 3 4 5 6 7 8 9 10
-do
-  sleep 1
-  grep "10.53.0.2.*\[cookie=" ns1/named_dump.db > /dev/null && break
-done
-grep "10.53.0.2.*\[cookie=" ns1/named_dump.db > /dev/null || ret=1
+rndc_dumpdb ns1
+grep "10.53.0.2.*\[cookie=" ns1/named_dump.db.test$n > /dev/null || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
 
diff --git a/bin/tests/system/dnssec/clean.sh b/bin/tests/system/dnssec/clean.sh
index c49ee9a1ac..bee3bbfd62 100644
--- a/bin/tests/system/dnssec/clean.sh
+++ b/bin/tests/system/dnssec/clean.sh
@@ -92,7 +92,7 @@ rm -f ./ns3/ttlpatch.example.db ./ns3/ttlpatch.example.db.signed
 rm -f ./ns3/ttlpatch.example.db.patched
 rm -f ./ns3/unsecure.example.db ./ns3/bogus.example.db ./ns3/keyless.example.db
 rm -f ./ns4/managed-keys.bind*
-rm -f ./ns4/named_dump.db
+rm -f ./ns4/named_dump.db*
 rm -f ./ns6/optout-tld.db
 rm -f ./ns7/multiple.example.bk ./ns7/nsec3.example.bk ./ns7/optout.example.bk
 rm -f ./ns7/split-rrsig.db ./ns7/split-rrsig.db.unsplit
diff --git a/bin/tests/system/dnssec/tests.sh b/bin/tests/system/dnssec/tests.sh
index a871bb7975..243b0a6426 100644
--- a/bin/tests/system/dnssec/tests.sh
+++ b/bin/tests/system/dnssec/tests.sh
@@ -3098,9 +3098,8 @@ status=$((status+ret))
 
 echo_i "check that key id are logged when dumping the cache ($n)"
 ret=0
-rndccmd 10.53.0.4 dumpdb 2>&1 | sed 's/^/ns4 /' | cat_i
-sleep 1
-grep "; key id = " ns4/named_dump.db > /dev/null || ret=1
+rndc_dumpdb ns4
+grep "; key id = " ns4/named_dump.db.test$n > /dev/null || ret=1
 n=$((n+1))
 test "$ret" -eq 0 || echo_i "failed"
 status=$((status+ret))
diff --git a/bin/tests/system/rndc/clean.sh b/bin/tests/system/rndc/clean.sh
index 3472273c27..ddab2df8fe 100644
--- a/bin/tests/system/rndc/clean.sh
+++ b/bin/tests/system/rndc/clean.sh
@@ -16,7 +16,7 @@ rm -f ns*/named.run ns*/named.run.prev
 rm -f ns2/named.stats
 rm -f ns2/nil.db ns2/other.db ns2/static.db ns2/*.jnl
 rm -f ns2/session.key
-rm -f ns3/named_dump.db
+rm -f ns3/named_dump.db*
 rm -f ns4/*.nta
 rm -f ns4/key?.conf
 rm -f ns6/huge.zone.db
diff --git a/bin/tests/system/rndc/tests.sh b/bin/tests/system/rndc/tests.sh
index 3718e14318..2af855aa28 100644
--- a/bin/tests/system/rndc/tests.sh
+++ b/bin/tests/system/rndc/tests.sh
@@ -314,15 +314,7 @@ status=`expr $status + $ret`
 n=`expr $n + 1`
 echo_i "test 'rndc dumpdb' on a empty cache ($n)"
 ret=0
-$RNDCCMD 10.53.0.3 dumpdb > /dev/null || ret=1
-for i in 1 2 3 4 5 6 7 8 9
-do
-	tmp=0
-	grep "Dump complete" ns3/named_dump.db > /dev/null || tmp=1
-	[ $tmp -eq 0 ] && break
-	sleep 1
-done
-[ $tmp -eq 1 ] && ret=1
+rndc_dumpdb ns3 || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
 
diff --git a/bin/tests/system/serve-stale/ns1/named1.conf.in b/bin/tests/system/serve-stale/ns1/named1.conf.in
index 5e7caec3fe..be3551aae9 100644
--- a/bin/tests/system/serve-stale/ns1/named1.conf.in
+++ b/bin/tests/system/serve-stale/ns1/named1.conf.in
@@ -27,7 +27,6 @@ options {
 	listen-on { 10.53.0.1; };
 	listen-on-v6 { none; };
 	recursion yes;
-	dump-file "named_dump1.db";
 	max-stale-ttl 3600;
 	stale-answer-ttl 2;
 	stale-answer-enable yes;
diff --git a/bin/tests/system/serve-stale/ns1/named2.conf.in b/bin/tests/system/serve-stale/ns1/named2.conf.in
index f330fd45cf..cdf1e9445d 100644
--- a/bin/tests/system/serve-stale/ns1/named2.conf.in
+++ b/bin/tests/system/serve-stale/ns1/named2.conf.in
@@ -26,7 +26,6 @@ options {
 	pid-file "named.pid";
 	listen-on { 10.53.0.1; };
 	listen-on-v6 { none; };
-	dump-file "named_dump1.db";
 	recursion yes;
 	max-stale-ttl 7200;
 	stale-answer-ttl 3;
diff --git a/bin/tests/system/serve-stale/tests.sh b/bin/tests/system/serve-stale/tests.sh
index a74b39efe0..01d3f210b6 100755
--- a/bin/tests/system/serve-stale/tests.sh
+++ b/bin/tests/system/serve-stale/tests.sh
@@ -96,15 +96,11 @@ grep "data\.example\..*2.*IN.*TXT.*A text record with a 1 second ttl" dig.out.te
 # Run rndc dumpdb, test whether the stale data has correct comment printed.
 # The max-stale-ttl is 3600 seconds, so the comment should say the data is
 # stale for somewhere between 3500-3599 seconds.
-$RNDCCMD 10.53.0.1 dumpdb > rndc.out.test$n 2>&1 || ret=1
-for i in 0 1 2 3 4 5 6 7 8 9; do
-	grep '^; Dump complete$' ns1/named_dump1.db > /dev/null 2>&1 && break
-	sleep 1
-done
-awk '/; stale/ { x=$0; getline; print x, $0}' ns1/named_dump1.db |
+rndc_dumpdb ns1 || ret=1
+awk '/; stale/ { x=$0; getline; print x, $0}' ns1/named_dump.db.test$n |
     grep "; stale (will be retained for 35.. more seconds) data\.example.*A text record with a 1 second ttl" > /dev/null 2>&1 || ret=1
 # Also make sure the not expired data does not have a stale comment.
-awk '/; answer/ { x=$0; getline; print x, $0}' ns1/named_dump1.db |
+awk '/; answer/ { x=$0; getline; print x, $0}' ns1/named_dump.db.test$n |
     grep "; answer longttl\.example.*A text record with a 600 second ttl" > /dev/null 2>&1 || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
diff --git a/bin/tests/system/sfcache/clean.sh b/bin/tests/system/sfcache/clean.sh
index 51939e98b0..75e55c18d8 100644
--- a/bin/tests/system/sfcache/clean.sh
+++ b/bin/tests/system/sfcache/clean.sh
@@ -17,7 +17,9 @@ rm -f ./*/named.memstats
 rm -f ./*/named.conf
 rm -f ./*/named.run ./*/named.run.prev
 rm -f ./dig.*
+rm -f ./rndc.*
 rm -f ./sfcache.*
+rm -f ./ns*/managed-keys.bind*
 rm -f ./ns*/named.lock
 rm -f ./ns5/named.run.part*
-rm -f ./ns*/managed-keys.bind*
+rm -f ./ns5/named_dump*
diff --git a/bin/tests/system/sfcache/tests.sh b/bin/tests/system/sfcache/tests.sh
index 19e34a724e..c512d6eea6 100644
--- a/bin/tests/system/sfcache/tests.sh
+++ b/bin/tests/system/sfcache/tests.sh
@@ -31,13 +31,8 @@ rndc_with_opts() {
 echo_i "checking DNSSEC SERVFAIL is cached ($n)"
 ret=0
 dig_with_opts +dnssec foo.example. a @10.53.0.5 > dig.out.ns5.test$n || ret=1
-rndc_with_opts 10.53.0.5 dumpdb -all 2>&1 | sed 's/^/I:ns5 /'
-# shellcheck disable=SC2034
-for i in 1 2 3 4 5 6 7 8 9 10; do
-    awk '/Zone/{out=0} { if (out) print } /SERVFAIL/{out=1}' ns5/named_dump.db > sfcache.$n
-    [ -s "sfcache.$n" ] && break
-    sleep 1
-done
+rndc_dumpdb ns5 -all
+awk '/Zone/{out=0} { if (out) print } /SERVFAIL/{out=1}' ns5/named_dump.db.test$n > sfcache.$n
 grep "^; foo.example/A" sfcache.$n > /dev/null || ret=1
 n=$((n+1))
 if [ $ret != 0 ]; then echo_i "failed"; fi
@@ -62,17 +57,16 @@ status=$((status+ret))
 echo_i "switching to non-dnssec SERVFAIL tests"
 ret=0
 rndc_with_opts 10.53.0.5 flush 2>&1 | sed 's/^/I:ns5 /'
-rndc_with_opts 10.53.0.5 dumpdb -all 2>&1 | sed 's/^/I:ns5 /'
-awk '/SERVFAIL/ { next; out=1 } /Zone/ { out=0 } { if (out) print }' ns5/named_dump.db
+rndc_dumpdb ns5 -all
+mv ns5/named_dump.db.test$n ns5/named_dump.db.test$n.1
+awk '/SERVFAIL/ { next; out=1 } /Zone/ { out=0 } { if (out) print }' ns5/named_dump.db.test$n.1 > sfcache.$n.1
+[ -s "sfcache.$n.1" ] && ret=1
 echo_i "checking SERVFAIL is cached ($n)"
 dig_with_opts bar.example2. a @10.53.0.5 > dig.out.ns5.test$n || ret=1
-for i in 1 2 3 4 5 6 7 8 9 10; do
-    rndc_with_opts 10.53.0.5 dumpdb -all 2>&1 | sed 's/^/I:ns5 /'
-    sleep 1
-    awk '/Zone/{out=0} { if (out) print } /SERVFAIL/{out=1}' ns5/named_dump.db > sfcache.$n
-    [ -s "sfcache.$n" ] && break
-done
-grep "^; bar.example2/A" sfcache.$n > /dev/null || ret=1
+rndc_dumpdb ns5 -all
+mv ns5/named_dump.db.test$n ns5/named_dump.db.test$n.2
+awk '/Zone/{out=0} { if (out) print } /SERVFAIL/{out=1}' ns5/named_dump.db.test$n.2 > sfcache.$n.2
+grep "^; bar.example2/A" sfcache.$n.2 > /dev/null || ret=1
 n=$((n+1))
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=$((status+ret))