diff --git a/testdata/blanks_cached_zone.tdir/blanks.example.com b/testdata/blanks_cached_zone.tdir/blanks.example.com.zone
similarity index 100%
rename from testdata/blanks_cached_zone.tdir/blanks.example.com
rename to testdata/blanks_cached_zone.tdir/blanks.example.com.zone
diff --git a/testdata/blanks_cached_zone.tdir/blanks_cached_zone.conf b/testdata/blanks_cached_zone.tdir/blanks_cached_zone.conf
index c3d43b79f..b0eb4aa9a 100644
--- a/testdata/blanks_cached_zone.tdir/blanks_cached_zone.conf
+++ b/testdata/blanks_cached_zone.tdir/blanks_cached_zone.conf
@@ -14,12 +14,7 @@ server:
 
 auth-zone:
         name: blanks.example.com
-        zonefile: "blanks.example.com"
-	url: "https://www.example.com/blanks.example.com.zone"
+        zonefile: "blanks.example.com.zone"
+	url: "https://127.0.0.1:@TOPORT@/blanks.example.com.zone"
 	for-upstream: yes
 	for-downstream: yes
-
-#rpz:
-#        name: blanks.example.com
-#        zonefile: "blanks.example.com"
-#	url: "https://127.0.0.1:@TOPORT@/blanks.example.com.zone"
diff --git a/testdata/blanks_cached_zone.tdir/blanks_cached_zone.pre b/testdata/blanks_cached_zone.tdir/blanks_cached_zone.pre
index 4a9f69bd6..f347a66cc 100644
--- a/testdata/blanks_cached_zone.tdir/blanks_cached_zone.pre
+++ b/testdata/blanks_cached_zone.tdir/blanks_cached_zone.pre
@@ -8,10 +8,11 @@ PRE="../.."
 . ../common.sh
 get_random_port 2
 UNBOUND_PORT=$RND_PORT
+UNUSED_PORT=$(($RND_PORT + 1))
 echo "UNBOUND_PORT=$UNBOUND_PORT" >> .tpkg.var.test
 
 # make config file
-sed -e 's/@PORT\@/'$UNBOUND_PORT'/' < blanks_cached_zone.conf > ub.conf
+sed -e 's/@PORT\@/'$UNBOUND_PORT'/' -e 's/@TOPORT\@/'$UNUSED_PORT'/' < blanks_cached_zone.conf > ub.conf
 # start unbound in the background
 $PRE/unbound -d -c ub.conf >unbound.log 2>&1 &
 UNBOUND_PID=$!