diff --git a/bin/tests/system/ixfr/prereq.sh b/bin/tests/system/ixfr/prereq.sh
index affe54bfcf..0e299f4db8 100644
--- a/bin/tests/system/ixfr/prereq.sh
+++ b/bin/tests/system/ixfr/prereq.sh
@@ -9,6 +9,9 @@
 # See the COPYRIGHT file distributed with this work for additional
 # information regarding copyright ownership.
 
+SYSTEMTESTTOP=..
+. $SYSTEMTESTTOP/conf.sh
+
 if $PERL -e 'use Net::DNS;' 2>/dev/null
 then
     :
diff --git a/bin/tests/system/statistics/prereq.sh b/bin/tests/system/statistics/prereq.sh
index 9bca4f871d..ec3fefe08a 100644
--- a/bin/tests/system/statistics/prereq.sh
+++ b/bin/tests/system/statistics/prereq.sh
@@ -9,6 +9,9 @@
 # See the COPYRIGHT file distributed with this work for additional
 # information regarding copyright ownership.
 
+SYSTEMTESTTOP=..
+. $SYSTEMTESTTOP/conf.sh
+
 if $PERL -e 'use Net::DNS;' 2>/dev/null
 then
     if $PERL -e 'use Net::DNS; die if ($Net::DNS::VERSION >= 0.76 && $Net::DNS::VERSION <= 0.77);' 2>/dev/null
diff --git a/bin/tests/system/statschannel/prereq.sh b/bin/tests/system/statschannel/prereq.sh
index ef052f5580..f3d4fd17a6 100644
--- a/bin/tests/system/statschannel/prereq.sh
+++ b/bin/tests/system/statschannel/prereq.sh
@@ -9,6 +9,9 @@
 # See the COPYRIGHT file distributed with this work for additional
 # information regarding copyright ownership.
 
+SYSTEMTESTTOP=..
+. $SYSTEMTESTTOP/conf.sh
+
 fail=0
 
 if $PERL -e 'use File::Fetch;' 2>/dev/null
diff --git a/bin/tests/system/upforwd/prereq.sh b/bin/tests/system/upforwd/prereq.sh
index affe54bfcf..0e299f4db8 100644
--- a/bin/tests/system/upforwd/prereq.sh
+++ b/bin/tests/system/upforwd/prereq.sh
@@ -9,6 +9,9 @@
 # See the COPYRIGHT file distributed with this work for additional
 # information regarding copyright ownership.
 
+SYSTEMTESTTOP=..
+. $SYSTEMTESTTOP/conf.sh
+
 if $PERL -e 'use Net::DNS;' 2>/dev/null
 then
     :
diff --git a/bin/tests/system/xfer/prereq.sh b/bin/tests/system/xfer/prereq.sh
index daa3d5d86c..b8982d610c 100644
--- a/bin/tests/system/xfer/prereq.sh
+++ b/bin/tests/system/xfer/prereq.sh
@@ -9,6 +9,9 @@
 # See the COPYRIGHT file distributed with this work for additional
 # information regarding copyright ownership.
 
+SYSTEMTESTTOP=..
+. $SYSTEMTESTTOP/conf.sh
+
 if $PERL -e 'use Net::DNS;' 2>/dev/null
 then
     if $PERL -e 'use Net::DNS; die if ($Net::DNS::VERSION >= 0.69 && $Net::DNS::VERSION <= 0.74);' 2>/dev/null