diff --git a/aux/btest b/aux/btest
index f2cfd177f7..4a7bb0f6d6 160000
--- a/aux/btest
+++ b/aux/btest
@@ -1 +1 @@
-Subproject commit f2cfd177f7ab6a9d78abf2254f382ae72ec393e2
+Subproject commit 4a7bb0f6d6c14175f6c7c63fd39f30b5f369e1cf
diff --git a/testing/btest/Baseline/broker.ssl_auth_failure/send.send.out b/testing/btest/Baseline/broker.ssl_auth_failure/send.send.out
index af1061d460..057a0f3d8e 100644
--- a/testing/btest/Baseline/broker.ssl_auth_failure/send.send.out
+++ b/testing/btest/Baseline/broker.ssl_auth_failure/send.send.out
@@ -1 +1 @@
-sender error: code=Broker::PEER_UNAVAILABLE msg=(invalid-node, *127.0.0.1:9999, "remote endpoint unavailable")
+sender error: code=Broker::PEER_UNAVAILABLE msg=(invalid-node, *<endpoint addr:port>, "remote endpoint unavailable")
diff --git a/testing/btest/Baseline/scripts.base.frameworks.netcontrol.acld-hook/send.send.out b/testing/btest/Baseline/scripts.base.frameworks.netcontrol.acld-hook/send.send.out
index b348f04fc0..acd91c327a 100644
--- a/testing/btest/Baseline/scripts.base.frameworks.netcontrol.acld-hook/send.send.out
+++ b/testing/btest/Baseline/scripts.base.frameworks.netcontrol.acld-hook/send.send.out
@@ -1,4 +1,4 @@
-Broker peer added, [address=127.0.0.1, bound_port=9999/tcp]
+Broker peer added, 127.0.0.1, T
 rule added, [ty=NetControl::FLOW, conn=<uninitialized>, flow=[src_h=192.168.18.50/32, src_p=<uninitialized>, dst_h=74.125.239.97/32, dst_p=<uninitialized>, src_m=<uninitialized>, dst_m=<uninitialized>], ip=<uninitialized>, mac=<uninitialized>], NetControl::DROP
 rule added, [ty=NetControl::FLOW, conn=<uninitialized>, flow=[src_h=<uninitialized>, src_p=<uninitialized>, dst_h=<uninitialized>, dst_p=443/tcp, src_m=<uninitialized>, dst_m=<uninitialized>], ip=<uninitialized>, mac=<uninitialized>], NetControl::DROP
 rule added, [ty=NetControl::ADDRESS, conn=<uninitialized>, flow=<uninitialized>, ip=192.168.18.50/32, mac=<uninitialized>], NetControl::DROP
diff --git a/testing/btest/Baseline/scripts.base.frameworks.netcontrol.acld/send.send.out b/testing/btest/Baseline/scripts.base.frameworks.netcontrol.acld/send.send.out
index 1e24b1ae3a..2c0b479dad 100644
--- a/testing/btest/Baseline/scripts.base.frameworks.netcontrol.acld/send.send.out
+++ b/testing/btest/Baseline/scripts.base.frameworks.netcontrol.acld/send.send.out
@@ -1,4 +1,4 @@
-Broker peer added, [address=127.0.0.1, bound_port=9999/tcp]
+Broker peer added, 127.0.0.1, T
 rule added, [ty=NetControl::FLOW, conn=<uninitialized>, flow=[src_h=192.168.18.50/32, src_p=<uninitialized>, dst_h=74.125.239.97/32, dst_p=<uninitialized>, src_m=<uninitialized>, dst_m=<uninitialized>], ip=<uninitialized>, mac=<uninitialized>], NetControl::DROP
 rule exists, [ty=NetControl::FLOW, conn=<uninitialized>, flow=[src_h=<uninitialized>, src_p=<uninitialized>, dst_h=<uninitialized>, dst_p=443/tcp, src_m=<uninitialized>, dst_m=<uninitialized>], ip=<uninitialized>, mac=<uninitialized>], NetControl::DROP
 rule added, [ty=NetControl::ADDRESS, conn=<uninitialized>, flow=<uninitialized>, ip=192.168.18.50/32, mac=<uninitialized>], NetControl::DROP
diff --git a/testing/btest/Baseline/scripts.base.frameworks.netcontrol.broker/send.send.out b/testing/btest/Baseline/scripts.base.frameworks.netcontrol.broker/send.send.out
index 920fdd8085..4b46d2487c 100644
--- a/testing/btest/Baseline/scripts.base.frameworks.netcontrol.broker/send.send.out
+++ b/testing/btest/Baseline/scripts.base.frameworks.netcontrol.broker/send.send.out
@@ -1,4 +1,4 @@
-Broker peer added, [address=127.0.0.1, bound_port=9999/tcp]
+Broker peer added, 127.0.0.1, T
 rule exists, [ty=NetControl::FLOW, conn=<uninitialized>, flow=[src_h=10.10.1.4/32, src_p=1470/tcp, dst_h=74.53.140.153/32, dst_p=25/tcp, src_m=<uninitialized>, dst_m=<uninitialized>], ip=<uninitialized>, mac=<uninitialized>], NetControl::DROP
 rule timeout, [ty=NetControl::FLOW, conn=<uninitialized>, flow=[src_h=10.10.1.4/32, src_p=1470/tcp, dst_h=74.53.140.153/32, dst_p=25/tcp, src_m=<uninitialized>, dst_m=<uninitialized>], ip=<uninitialized>, mac=<uninitialized>], NetControl::DROP, [duration=<uninitialized>, packet_count=<uninitialized>, byte_count=<uninitialized>]
 rule added, [ty=NetControl::ADDRESS, conn=<uninitialized>, flow=<uninitialized>, ip=10.10.1.4/32, mac=<uninitialized>], NetControl::DROP
diff --git a/testing/btest/Baseline/scripts.base.frameworks.openflow.broker-basic/send.send.out b/testing/btest/Baseline/scripts.base.frameworks.openflow.broker-basic/send.send.out
index ec860918ba..a416783950 100644
--- a/testing/btest/Baseline/scripts.base.frameworks.openflow.broker-basic/send.send.out
+++ b/testing/btest/Baseline/scripts.base.frameworks.openflow.broker-basic/send.send.out
@@ -1,4 +1,4 @@
-Broker peer added, [address=127.0.0.1, bound_port=9999/tcp]
+Broker peer added, 127.0.0.1, T
 Flow_mod_success
 Flow_mod_failure
 connection established
diff --git a/testing/btest/broker/connect-on-retry.bro b/testing/btest/broker/connect-on-retry.bro
index 200dc5abd6..56e479b7ea 100644
--- a/testing/btest/broker/connect-on-retry.bro
+++ b/testing/btest/broker/connect-on-retry.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 #
 # @TEST-EXEC: btest-bg-run recv "bro -B broker -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -B broker -b ../send.bro >send.out"
@@ -20,7 +20,7 @@ event bro_init()
     {
     Broker::subscribe("bro/event/my_topic");
     Broker::auto_publish("bro/event/my_topic", ping);
-    Broker::peer("127.0.0.1");
+    Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
     }
 
 function send_event()
@@ -62,7 +62,7 @@ global pong: event(msg: string, c: count);
 
 event delayed_listen()
 	{
-        Broker::listen("127.0.0.1");
+        Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event bro_init()
diff --git a/testing/btest/broker/disconnect.bro b/testing/btest/broker/disconnect.bro
index 3dd2dc45d4..08d80f0441 100644
--- a/testing/btest/broker/disconnect.bro
+++ b/testing/btest/broker/disconnect.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 
 # @TEST-EXEC: btest-bg-run recv "bro -B broker -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -B broker -b ../send.bro >send.out"
@@ -27,7 +27,7 @@ event my_event(i: count)
 event bro_init()
 	{
 	Broker::subscribe(test_topic);
-	Broker::peer("127.0.0.1");
+	Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_lost(endpoint: Broker::EndpointInfo, msg: string)
@@ -63,7 +63,7 @@ event my_event(i: count)
 event bro_init()
 	{
 	Broker::subscribe(test_topic);
-	Broker::listen("127.0.0.1");
+	Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_lost(endpoint: Broker::EndpointInfo, msg: string)
diff --git a/testing/btest/broker/error.bro b/testing/btest/broker/error.bro
index af94e28019..aa413ea2ac 100644
--- a/testing/btest/broker/error.bro
+++ b/testing/btest/broker/error.bro
@@ -1,5 +1,3 @@
-# @TEST-SERIALIZE: comm
-#
 # @TEST-EXEC: bro -B main-loop,broker -b send.bro >send.out
 # @TEST-EXEC: btest-diff send.out
 # 
diff --git a/testing/btest/broker/remote_event.bro b/testing/btest/broker/remote_event.bro
index 1cb6fbd1ae..a9e22ec25f 100644
--- a/testing/btest/broker/remote_event.bro
+++ b/testing/btest/broker/remote_event.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 #
 # @TEST-EXEC: btest-bg-run recv "bro -B broker -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -B broker -b ../send.bro >send.out"
@@ -18,7 +18,7 @@ global ping: event(msg: string, c: count);
 event bro_init()
     {
     Broker::subscribe("bro/event/my_topic");
-    Broker::peer("127.0.0.1");
+    Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
     print "is_remote should be F, and is", is_remote_event();
     }
 
@@ -67,7 +67,7 @@ global pong: event(msg: string, c: count);
 event bro_init()
         {
         Broker::subscribe("bro/event/my_topic");
-        Broker::listen("127.0.0.1");
+        Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
         }
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
diff --git a/testing/btest/broker/remote_event_any.bro b/testing/btest/broker/remote_event_any.bro
index a71261f889..b45e5017ef 100644
--- a/testing/btest/broker/remote_event_any.bro
+++ b/testing/btest/broker/remote_event_any.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 #
 # @TEST-EXEC: btest-bg-run recv "bro -B broker -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -B broker -b ../send.bro >send.out"
@@ -18,7 +18,7 @@ global ping: event(msg: string, c: any);
 event bro_init()
     {
     Broker::subscribe("bro/event/my_topic");
-    Broker::peer("127.0.0.1");
+    Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
     print "is_remote should be F, and is", is_remote_event();
     }
 
@@ -70,7 +70,7 @@ global pong: event(msg: string, c: any);
 event bro_init()
         {
         Broker::subscribe("bro/event/my_topic");
-        Broker::listen("127.0.0.1");
+        Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
         }
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
diff --git a/testing/btest/broker/remote_event_auto.bro b/testing/btest/broker/remote_event_auto.bro
index ec060b4cf5..04570b9e6d 100644
--- a/testing/btest/broker/remote_event_auto.bro
+++ b/testing/btest/broker/remote_event_auto.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 #
 # @TEST-EXEC: btest-bg-run recv "bro -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -b ../send.bro >send.out"
@@ -19,7 +19,7 @@ event bro_init()
     {
     Broker::subscribe("bro/event/my_topic");
     Broker::auto_publish("bro/event/my_topic", ping);
-    Broker::peer("127.0.0.1");
+    Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
     }
 
 function send_event()
@@ -63,7 +63,7 @@ event bro_init()
         {
         Broker::subscribe("bro/event/my_topic");
 	Broker::auto_publish("bro/event/my_topic", pong);
-        Broker::listen("127.0.0.1");
+        Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
         }
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
diff --git a/testing/btest/broker/remote_event_ssl_auth.bro b/testing/btest/broker/remote_event_ssl_auth.bro
index 0c9335d803..2422638416 100644
--- a/testing/btest/broker/remote_event_ssl_auth.bro
+++ b/testing/btest/broker/remote_event_ssl_auth.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 #
 # @TEST-EXEC: btest-bg-run recv "bro -B broker -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -B broker -b ../send.bro >send.out"
@@ -177,7 +177,7 @@ global ping: event(msg: string, c: count);
 event bro_init()
     {
     Broker::subscribe("bro/event/my_topic");
-    Broker::peer("127.0.0.1");
+    Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
     }
 
 function send_event()
@@ -228,7 +228,7 @@ global pong: event(msg: string, c: count);
 event bro_init()
         {
         Broker::subscribe("bro/event/my_topic");
-        Broker::listen("127.0.0.1");
+        Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
         }
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
diff --git a/testing/btest/broker/remote_event_vector_any.bro b/testing/btest/broker/remote_event_vector_any.bro
index 25ac8cf5a2..6f03d97c56 100644
--- a/testing/btest/broker/remote_event_vector_any.bro
+++ b/testing/btest/broker/remote_event_vector_any.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 #
 # @TEST-EXEC: btest-bg-run recv "bro -B broker -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -B broker -b ../send.bro >send.out"
@@ -23,7 +23,7 @@ global bar: event(x: any);
 event bro_init()
 	{
 	Broker::subscribe("test");
-	Broker::peer("127.0.0.1");
+	Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
@@ -94,7 +94,7 @@ event bar(x: any)
 event bro_init()
 	{
 	Broker::subscribe("test");
-	Broker::listen();
+	Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_lost(endpoint: Broker::EndpointInfo, msg: string)
diff --git a/testing/btest/broker/remote_id.bro b/testing/btest/broker/remote_id.bro
index bf73e7e125..62cddb9f25 100644
--- a/testing/btest/broker/remote_id.bro
+++ b/testing/btest/broker/remote_id.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 #
 # @TEST-EXEC: btest-bg-run recv "bro -B broker -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -B broker -b ../send.bro test_var=newval >send.out"
@@ -12,7 +12,7 @@ const test_var = "init" &redef;
 
 event bro_init()
 	{
-	Broker::peer("127.0.0.1");
+	Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_lost(endpoint: Broker::EndpointInfo, msg: string)
@@ -48,7 +48,7 @@ event bro_init()
 	{
 	print "intial val", test_var;
 	Broker::subscribe("bro/ids");
-	Broker::listen();
+	Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
diff --git a/testing/btest/broker/remote_log.bro b/testing/btest/broker/remote_log.bro
index 0f20ab7542..dae89d42b2 100644
--- a/testing/btest/broker/remote_log.bro
+++ b/testing/btest/broker/remote_log.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 
 # @TEST-EXEC: btest-bg-run recv "bro -B broker -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -B broker -b ../send.bro >send.out"
@@ -45,7 +45,7 @@ event Broker::peer_lost(endpoint: Broker::EndpointInfo, msg: string)
 event bro_init()
 	{
 	Broker::subscribe("bro/");
-	Broker::listen("127.0.0.1");
+	Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_removed(endpoint: Broker::EndpointInfo, msg: string)
@@ -63,7 +63,7 @@ event Broker::peer_removed(endpoint: Broker::EndpointInfo, msg: string)
 
 event bro_init()
 	{
-	Broker::peer("127.0.0.1");
+	Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 global n = 0;
diff --git a/testing/btest/broker/remote_log_late_join.bro b/testing/btest/broker/remote_log_late_join.bro
index 8f2eae45b5..aea7846996 100644
--- a/testing/btest/broker/remote_log_late_join.bro
+++ b/testing/btest/broker/remote_log_late_join.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 
 # @TEST-EXEC: btest-bg-run recv "bro -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -b ../send.bro >send.out"
@@ -45,7 +45,7 @@ event Broker::peer_lost(endpoint: Broker::EndpointInfo, msg: string)
 event bro_init()
 	{
 	Broker::subscribe("bro/");
-	Broker::listen("127.0.0.1");
+	Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_removed(endpoint: Broker::EndpointInfo, msg: string)
@@ -63,7 +63,7 @@ event Broker::peer_removed(endpoint: Broker::EndpointInfo, msg: string)
 
 event doconnect()
 	{
-	Broker::peer("127.0.0.1");
+	Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 global n = 0;
diff --git a/testing/btest/broker/remote_log_types.bro b/testing/btest/broker/remote_log_types.bro
index b965e0928a..8bbc66eaa2 100644
--- a/testing/btest/broker/remote_log_types.bro
+++ b/testing/btest/broker/remote_log_types.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 
 # @TEST-EXEC: btest-bg-run recv "bro -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -b ../send.bro >send.out"
@@ -61,7 +61,7 @@ event bro_init() &priority=5
 event bro_init()
 	{
 	Broker::subscribe("bro/");
-	Broker::listen("127.0.0.1");
+	Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event quit_receiver()
@@ -79,7 +79,7 @@ event quit_receiver()
 
 event bro_init()
 	{
-	Broker::peer("127.0.0.1");
+	Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event quit_sender()
diff --git a/testing/btest/broker/ssl_auth_failure.bro b/testing/btest/broker/ssl_auth_failure.bro
index d78edd0ac3..bc90d86298 100644
--- a/testing/btest/broker/ssl_auth_failure.bro
+++ b/testing/btest/broker/ssl_auth_failure.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 #
 # @TEST-EXEC: btest-bg-run recv "bro -B broker -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -B broker -b ../send.bro >send.out"
@@ -106,7 +106,7 @@ event do_terminate()
 event bro_init()
     {
     Broker::subscribe("bro/event/my_topic");
-    Broker::peer("127.0.0.1");
+    Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
     schedule 5secs { do_terminate()   };
     }
 
@@ -123,7 +123,7 @@ event Broker::peer_lost(endpoint: Broker::EndpointInfo, msg: string)
 
 event Broker::error(code: Broker::ErrorCode, msg: string)
     {
-    print fmt("sender error: code=%s msg=%s", code, msg);
+    print fmt("sender error: code=%s msg=%s", code, gsub(msg, /127.0.0.1:[0-9]+/, "<endpoint addr:port>"));
     terminate();
     }
 
@@ -147,7 +147,7 @@ event do_terminate()
 
 event bro_init()
         {
-        Broker::listen("127.0.0.1");
+        Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
         schedule 10secs { do_terminate()   };
         }
 
diff --git a/testing/btest/broker/store/clone.bro b/testing/btest/broker/store/clone.bro
index 0865e55923..5620303410 100644
--- a/testing/btest/broker/store/clone.bro
+++ b/testing/btest/broker/store/clone.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 #
 # @TEST-EXEC: btest-bg-run clone "bro -B broker -b  ../clone-main.bro >clone.out"
 # @TEST-EXEC: btest-bg-run master "bro -B broker -b  ../master-main.bro >master.out"
@@ -58,7 +58,7 @@ event bro_init()
 	Broker::put(h, "two", 223);
 	Broker::put(h, vector(1,2), 1947/tcp);
 	
-	Broker::peer("127.0.0.1");
+	Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event insert_more()
@@ -133,7 +133,7 @@ event bro_init()
 	{
 	Broker::auto_publish("bro/events", inserted);
 	Broker::subscribe("bro/");
-	Broker::listen("127.0.0.1");
+	Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
diff --git a/testing/btest/broker/unpeer.bro b/testing/btest/broker/unpeer.bro
index 1165799488..b591815955 100644
--- a/testing/btest/broker/unpeer.bro
+++ b/testing/btest/broker/unpeer.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 #
 # @TEST-EXEC: btest-bg-run recv "bro -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -b ../send.bro >send.out"
@@ -38,7 +38,7 @@ event bro_init()
     {
     Broker::subscribe("bro/event/my_topic");
     Broker::auto_publish("bro/event/my_topic", print_something);
-    Broker::peer("127.0.0.1");
+    Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
     }
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
@@ -68,7 +68,7 @@ event print_something(i: int)
 event bro_init()
     {
     Broker::subscribe("bro/event/my_topic");
-    Broker::listen("127.0.0.1");
+    Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
     schedule 10secs { do_terminate() };
     }
 
diff --git a/testing/btest/core/leaks/basic-cluster.bro b/testing/btest/core/leaks/basic-cluster.bro
index 57552c54af..fa73fb9a96 100644
--- a/testing/btest/core/leaks/basic-cluster.bro
+++ b/testing/btest/core/leaks/basic-cluster.bro
@@ -1,6 +1,8 @@
 # Needs perftools support.
 #
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
 # @TEST-GROUP: leaks
 #
 # @TEST-REQUIRES: bro  --help 2>&1 | grep -q mem-leaks
@@ -12,9 +14,9 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1", $interface="eth0"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/core/leaks/broker/clone_store.bro b/testing/btest/core/leaks/broker/clone_store.bro
index 2cd728c631..68235c7bab 100644
--- a/testing/btest/core/leaks/broker/clone_store.bro
+++ b/testing/btest/core/leaks/broker/clone_store.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 # @TEST-REQUIRES: bro --help 2>&1 | grep -q mem-leaks
 # @TEST-GROUP: leaks
 
@@ -59,7 +59,7 @@ event bro_init()
 	Broker::put(h, "two", 223);
 	Broker::put(h, vector(1,2), 1947/tcp);
 	
-	Broker::peer("127.0.0.1");
+	Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event insert_more()
@@ -131,7 +131,7 @@ event bro_init()
 	{
 	Broker::auto_publish("bro/events", inserted);
 	Broker::subscribe("bro/");
-	Broker::listen("127.0.0.1");
+	Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
diff --git a/testing/btest/core/leaks/broker/remote_event.test b/testing/btest/core/leaks/broker/remote_event.test
index b788f3ee79..e11d083db3 100644
--- a/testing/btest/core/leaks/broker/remote_event.test
+++ b/testing/btest/core/leaks/broker/remote_event.test
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 # @TEST-REQUIRES: bro --help 2>&1 | grep -q mem-leaks
 # @TEST-GROUP: leaks
 
@@ -20,7 +20,7 @@ event bro_init()
 	{
 	Broker::subscribe("bro/event/");
 	Broker::auto_publish("bro/event/my_topic", auto_event_handler);
-	Broker::listen("127.0.0.1");
+	Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 global event_count = 0;
@@ -53,7 +53,7 @@ global auto_event_handler: event(msg: string, c: count);
 event bro_init()
 	{
 	Broker::subscribe("bro/event/my_topic");
-	Broker::peer("127.0.0.1", Broker::default_port, 1secs);
+	Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")), 1secs);
 	}
 
 global event_count = 0;
diff --git a/testing/btest/core/leaks/broker/remote_log.test b/testing/btest/core/leaks/broker/remote_log.test
index a2b1d8793e..4d55705e4a 100644
--- a/testing/btest/core/leaks/broker/remote_log.test
+++ b/testing/btest/core/leaks/broker/remote_log.test
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 # @TEST-REQUIRES: bro --help 2>&1 | grep -q mem-leaks
 # @TEST-GROUP: leaks
 
@@ -46,7 +46,7 @@ event Broker::peer_lost(endpoint: Broker::EndpointInfo, msg: string)
 event bro_init()
 	{
 	Broker::subscribe("bro/");
-	Broker::listen("127.0.0.1");
+	Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_removed(endpoint: Broker::EndpointInfo, msg: string)
@@ -62,7 +62,7 @@ event Broker::peer_removed(endpoint: Broker::EndpointInfo, msg: string)
 
 event bro_init()
 	{
-	Broker::peer("127.0.0.1");
+	Broker::peer("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 global n = 0;
diff --git a/testing/btest/core/leaks/hll_cluster.bro b/testing/btest/core/leaks/hll_cluster.bro
index 8b96c991b3..e565778fbc 100644
--- a/testing/btest/core/leaks/hll_cluster.bro
+++ b/testing/btest/core/leaks/hll_cluster.bro
@@ -1,6 +1,8 @@
 # Needs perftools support.
 #
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
 # @TEST-GROUP: leaks
 #
 # @TEST-REQUIRES: bro  --help 2>&1 | grep -q mem-leaks
@@ -17,9 +19,9 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/doc/broxygen/all_scripts.test b/testing/btest/doc/broxygen/all_scripts.test
index dc009044da..238ba3a4f3 100644
--- a/testing/btest/doc/broxygen/all_scripts.test
+++ b/testing/btest/doc/broxygen/all_scripts.test
@@ -4,8 +4,8 @@
 # This must be serialized with communication tests because it does load
 # listen.bro in order to document it.
 
-# @TEST-SERIALIZE: comm
-# @TEST-EXEC: unset BRO_DISABLE_BROXYGEN; bro -X broxygen.config broxygen DumpEvents::include=/NOTHING_MATCHES/
+# @TEST-PORT: BROKER_PORT
+# @TEST-EXEC: unset BRO_DISABLE_BROXYGEN; bro -X broxygen.config broxygen DumpEvents::include=/NOTHING_MATCHES/ Broker::default_port=$BROKER_PORT
 # @TEST-EXEC: btest-diff .stdout
 # @TEST-EXEC: TEST_DIFF_CANONIFIER=$SCRIPTS/diff-remove-abspath btest-diff .stderr
 
diff --git a/testing/btest/doc/broxygen/identifier.bro b/testing/btest/doc/broxygen/identifier.bro
index 9225ab8db0..ae49d812a0 100644
--- a/testing/btest/doc/broxygen/identifier.bro
+++ b/testing/btest/doc/broxygen/identifier.bro
@@ -1,5 +1,5 @@
-# @TEST-SERIALIZE: comm
-# @TEST-EXEC: unset BRO_DISABLE_BROXYGEN; bro -b -X broxygen.config %INPUT
+# @TEST-PORT: BROKER_PORT
+# @TEST-EXEC: unset BRO_DISABLE_BROXYGEN; bro -b -X broxygen.config %INPUT Broker::default_port=$BROKER_PORT
 # @TEST-EXEC: btest-diff test.rst
 
 @TEST-START-FILE broxygen.config
diff --git a/testing/btest/doc/broxygen/package.bro b/testing/btest/doc/broxygen/package.bro
index 0d8d790361..6a9957804a 100644
--- a/testing/btest/doc/broxygen/package.bro
+++ b/testing/btest/doc/broxygen/package.bro
@@ -1,5 +1,5 @@
-# @TEST-SERIALIZE: comm
-# @TEST-EXEC: unset BRO_DISABLE_BROXYGEN; bro -b -X broxygen.config %INPUT
+# @TEST-PORT: BROKER_PORT
+# @TEST-EXEC: unset BRO_DISABLE_BROXYGEN; bro -b -X broxygen.config %INPUT Broker::default_port=$BROKER_PORT
 # @TEST-EXEC: btest-diff test.rst
 
 @TEST-START-FILE broxygen.config
diff --git a/testing/btest/doc/broxygen/package_index.bro b/testing/btest/doc/broxygen/package_index.bro
index 4b98290f20..49c367aa48 100644
--- a/testing/btest/doc/broxygen/package_index.bro
+++ b/testing/btest/doc/broxygen/package_index.bro
@@ -1,5 +1,5 @@
-# @TEST-SERIALIZE: comm
-# @TEST-EXEC: unset BRO_DISABLE_BROXYGEN; bro -b -X broxygen.config %INPUT
+# @TEST-PORT: BROKER_PORT
+# @TEST-EXEC: unset BRO_DISABLE_BROXYGEN; bro -b -X broxygen.config %INPUT Broker::default_port=$BROKER_PORT
 # @TEST-EXEC: btest-diff test.rst
 
 @TEST-START-FILE broxygen.config
diff --git a/testing/btest/doc/broxygen/script_index.bro b/testing/btest/doc/broxygen/script_index.bro
index c987c005be..ab257ad35d 100644
--- a/testing/btest/doc/broxygen/script_index.bro
+++ b/testing/btest/doc/broxygen/script_index.bro
@@ -1,5 +1,5 @@
-# @TEST-SERIALIZE: comm
-# @TEST-EXEC: unset BRO_DISABLE_BROXYGEN; bro -b -X broxygen.config %INPUT
+# @TEST-PORT: BROKER_PORT
+# @TEST-EXEC: unset BRO_DISABLE_BROXYGEN; bro -b -X broxygen.config %INPUT Broker::default_port=$BROKER_PORT
 # @TEST-EXEC: btest-diff test.rst
 
 @TEST-START-FILE broxygen.config
diff --git a/testing/btest/doc/broxygen/script_summary.bro b/testing/btest/doc/broxygen/script_summary.bro
index 7fc89c3735..a517a08072 100644
--- a/testing/btest/doc/broxygen/script_summary.bro
+++ b/testing/btest/doc/broxygen/script_summary.bro
@@ -1,5 +1,5 @@
-# @TEST-SERIALIZE: comm
-# @TEST-EXEC: unset BRO_DISABLE_BROXYGEN; bro -b -X broxygen.config %INPUT
+# @TEST-PORT: BROKER_PORT
+# @TEST-EXEC: unset BRO_DISABLE_BROXYGEN; bro -b -X broxygen.config %INPUT Broker::default_port=$BROKER_PORT
 # @TEST-EXEC: btest-diff test.rst
 
 @TEST-START-FILE broxygen.config
diff --git a/testing/btest/language/when.bro b/testing/btest/language/when.bro
index 795552a422..a2bad6a620 100644
--- a/testing/btest/language/when.bro
+++ b/testing/btest/language/when.bro
@@ -1,4 +1,3 @@
-# @TEST-SERIALIZE: comm
 # @TEST-EXEC: btest-bg-run test1 bro %INPUT
 # @TEST-EXEC: btest-bg-wait 10
 # @TEST-EXEC: mv test1/.stdout out
diff --git a/testing/btest/scripts/base/frameworks/cluster/custom_pool_exclusivity.bro b/testing/btest/scripts/base/frameworks/cluster/custom_pool_exclusivity.bro
index 224b259e20..dc2558f2a4 100644
--- a/testing/btest/scripts/base/frameworks/cluster/custom_pool_exclusivity.bro
+++ b/testing/btest/scripts/base/frameworks/cluster/custom_pool_exclusivity.bro
@@ -1,4 +1,8 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
+# @TEST-PORT: BROKER_PORT4
+# @TEST-PORT: BROKER_PORT5
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run proxy-1   BROPATH=$BROPATH:.. CLUSTER_NODE=proxy-1 bro %INPUT
@@ -8,11 +12,11 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=37758/tcp, $manager="manager-1"],
-	["proxy-2"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=37759/tcp, $manager="manager-1"],
-	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1"],
+	["proxy-2"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1"],
+	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT4")), $manager="manager-1", $interface="eth0"],
+	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT5")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/cluster/custom_pool_limits.bro b/testing/btest/scripts/base/frameworks/cluster/custom_pool_limits.bro
index f5a9fed5b3..08202bd727 100644
--- a/testing/btest/scripts/base/frameworks/cluster/custom_pool_limits.bro
+++ b/testing/btest/scripts/base/frameworks/cluster/custom_pool_limits.bro
@@ -1,4 +1,8 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
+# @TEST-PORT: BROKER_PORT4
+# @TEST-PORT: BROKER_PORT5
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run proxy-1   BROPATH=$BROPATH:.. CLUSTER_NODE=proxy-1 bro %INPUT
@@ -8,11 +12,11 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=37758/tcp, $manager="manager-1"],
-	["proxy-2"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=37759/tcp, $manager="manager-1"],
-	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1"],
+	["proxy-2"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1"],
+	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT4")), $manager="manager-1", $interface="eth0"],
+	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT5")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/cluster/forwarding.bro b/testing/btest/scripts/base/frameworks/cluster/forwarding.bro
index db60b48a05..e62a2ced66 100644
--- a/testing/btest/scripts/base/frameworks/cluster/forwarding.bro
+++ b/testing/btest/scripts/base/frameworks/cluster/forwarding.bro
@@ -1,4 +1,8 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
+# @TEST-PORT: BROKER_PORT4
+# @TEST-PORT: BROKER_PORT5
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run proxy-1   BROPATH=$BROPATH:.. CLUSTER_NODE=proxy-1 bro %INPUT
@@ -14,11 +18,11 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=37758/tcp, $manager="manager-1"],
-	["proxy-2"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=37759/tcp, $manager="manager-1"],
-	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1"],
+	["proxy-2"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1"],
+	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT4")), $manager="manager-1", $interface="eth0"],
+	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT5")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/cluster/log_distribution.bro b/testing/btest/scripts/base/frameworks/cluster/log_distribution.bro
index bfdddc9497..199e265674 100644
--- a/testing/btest/scripts/base/frameworks/cluster/log_distribution.bro
+++ b/testing/btest/scripts/base/frameworks/cluster/log_distribution.bro
@@ -1,4 +1,7 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
+# @TEST-PORT: BROKER_PORT4
 #
 # @TEST-EXEC: btest-bg-run logger-1 BROPATH=$BROPATH:.. CLUSTER_NODE=logger-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run logger-2 BROPATH=$BROPATH:.. CLUSTER_NODE=logger-2 bro %INPUT
@@ -12,10 +15,10 @@
 redef Cluster::manager_is_logger = F;
 
 redef Cluster::nodes = {
-    ["manager"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-    ["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37760/tcp, $manager="manager", $interface="eth0"],
-    ["logger-1"] = [$node_type=Cluster::LOGGER,   $ip=127.0.0.1, $p=37762/tcp, $manager="manager"],
-    ["logger-2"] = [$node_type=Cluster::LOGGER,   $ip=127.0.0.1, $p=37763/tcp, $manager="manager"]
+    ["manager"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+    ["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager", $interface="eth0"],
+    ["logger-1"] = [$node_type=Cluster::LOGGER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager"],
+    ["logger-2"] = [$node_type=Cluster::LOGGER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT4")), $manager="manager"]
 };
 
 @TEST-END-FILE
diff --git a/testing/btest/scripts/base/frameworks/cluster/start-it-up-logger.bro b/testing/btest/scripts/base/frameworks/cluster/start-it-up-logger.bro
index 164eb0c1cb..d94875e858 100644
--- a/testing/btest/scripts/base/frameworks/cluster/start-it-up-logger.bro
+++ b/testing/btest/scripts/base/frameworks/cluster/start-it-up-logger.bro
@@ -1,4 +1,9 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
+# @TEST-PORT: BROKER_PORT4
+# @TEST-PORT: BROKER_PORT5
+# @TEST-PORT: BROKER_PORT6
 #
 # @TEST-EXEC: btest-bg-run logger-1  CLUSTER_NODE=logger-1  BROPATH=$BROPATH:.. bro %INPUT
 # @TEST-EXEC: btest-bg-run manager-1 CLUSTER_NODE=manager-1 BROPATH=$BROPATH:.. bro %INPUT
@@ -17,12 +22,12 @@
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::manager_is_logger = F;
 redef Cluster::nodes = {
-	["logger-1"] = [$node_type=Cluster::LOGGER,   $ip=127.0.0.1, $p=37757/tcp],
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37758/tcp],
-	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=37759/tcp, $manager="manager-1"],
-	["proxy-2"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1"],
-	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37762/tcp, $manager="manager-1", $interface="eth1"],
+	["logger-1"] = [$node_type=Cluster::LOGGER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2"))],
+	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1"],
+	["proxy-2"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT4")), $manager="manager-1"],
+	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT5")), $manager="manager-1", $interface="eth0"],
+	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT6")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/cluster/start-it-up.bro b/testing/btest/scripts/base/frameworks/cluster/start-it-up.bro
index aa4bcb45e4..eee6c29215 100644
--- a/testing/btest/scripts/base/frameworks/cluster/start-it-up.bro
+++ b/testing/btest/scripts/base/frameworks/cluster/start-it-up.bro
@@ -1,4 +1,8 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
+# @TEST-PORT: BROKER_PORT4
+# @TEST-PORT: BROKER_PORT5
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run proxy-1   BROPATH=$BROPATH:.. CLUSTER_NODE=proxy-1 bro %INPUT
@@ -14,11 +18,11 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=37758/tcp, $manager="manager-1"],
-	["proxy-2"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=37759/tcp, $manager="manager-1"],
-	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1"],
+	["proxy-2"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1"],
+	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT4")), $manager="manager-1", $interface="eth0"],
+	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT5")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/cluster/topic_distribution.bro b/testing/btest/scripts/base/frameworks/cluster/topic_distribution.bro
index 0116d6c231..317a38fbaa 100644
--- a/testing/btest/scripts/base/frameworks/cluster/topic_distribution.bro
+++ b/testing/btest/scripts/base/frameworks/cluster/topic_distribution.bro
@@ -1,4 +1,8 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
+# @TEST-PORT: BROKER_PORT4
+# @TEST-PORT: BROKER_PORT5
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run proxy-1   BROPATH=$BROPATH:.. CLUSTER_NODE=proxy-1 bro %INPUT
@@ -8,11 +12,11 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=37758/tcp, $manager="manager-1"],
-	["proxy-2"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=37759/tcp, $manager="manager-1"],
-	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1"],
+	["proxy-2"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1"],
+	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT4")), $manager="manager-1", $interface="eth0"],
+	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT5")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/cluster/topic_distribution_bifs.bro b/testing/btest/scripts/base/frameworks/cluster/topic_distribution_bifs.bro
index b9dd87e560..35ed52f883 100644
--- a/testing/btest/scripts/base/frameworks/cluster/topic_distribution_bifs.bro
+++ b/testing/btest/scripts/base/frameworks/cluster/topic_distribution_bifs.bro
@@ -1,4 +1,8 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
+# @TEST-PORT: BROKER_PORT4
+# @TEST-PORT: BROKER_PORT5
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run proxy-1   BROPATH=$BROPATH:.. CLUSTER_NODE=proxy-1 bro %INPUT
@@ -10,11 +14,11 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=37758/tcp, $manager="manager-1"],
-	["proxy-2"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=37759/tcp, $manager="manager-1"],
-	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1"],
+	["proxy-2"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1"],
+	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT4")), $manager="manager-1", $interface="eth0"],
+	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT5")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/config/basic_cluster.bro b/testing/btest/scripts/base/frameworks/config/basic_cluster.bro
index 6423773b26..99f1de8aeb 100644
--- a/testing/btest/scripts/base/frameworks/config/basic_cluster.bro
+++ b/testing/btest/scripts/base/frameworks/config/basic_cluster.bro
@@ -1,5 +1,7 @@
-# @TEST-SERIALIZE: comm
-# 
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
+#
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: sleep 1
 # @TEST-EXEC: btest-bg-run worker-1  BROPATH=$BROPATH:.. CLUSTER_NODE=worker-1 bro %INPUT
@@ -15,9 +17,9 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1", $interface="eth0"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/config/cluster_resend.bro b/testing/btest/scripts/base/frameworks/config/cluster_resend.bro
index e5c871a578..c66d5b2ba2 100644
--- a/testing/btest/scripts/base/frameworks/config/cluster_resend.bro
+++ b/testing/btest/scripts/base/frameworks/config/cluster_resend.bro
@@ -1,5 +1,7 @@
-# @TEST-SERIALIZE: comm
-# 
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
+#
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: sleep 1
 # @TEST-EXEC: btest-bg-run worker-1  BROPATH=$BROPATH:.. CLUSTER_NODE=worker-1 bro %INPUT
@@ -19,9 +21,9 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1", $interface="eth0"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/config/read_config_cluster.bro b/testing/btest/scripts/base/frameworks/config/read_config_cluster.bro
index ea806fc18c..3f77a0fdc3 100644
--- a/testing/btest/scripts/base/frameworks/config/read_config_cluster.bro
+++ b/testing/btest/scripts/base/frameworks/config/read_config_cluster.bro
@@ -1,4 +1,6 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
 # 
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: sleep 1
@@ -15,9 +17,9 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1", $interface="eth0"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/control/configuration_update.bro b/testing/btest/scripts/base/frameworks/control/configuration_update.bro
index d6f229d7a7..e90151bcbb 100644
--- a/testing/btest/scripts/base/frameworks/control/configuration_update.bro
+++ b/testing/btest/scripts/base/frameworks/control/configuration_update.bro
@@ -1,7 +1,7 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 #
-# @TEST-EXEC: btest-bg-run controllee  BROPATH=$BROPATH:.. bro -Bbroker %INPUT frameworks/control/controllee Broker::default_port=65531/tcp
-# @TEST-EXEC: btest-bg-run controller  BROPATH=$BROPATH:.. bro -Bbroker %INPUT test-redef frameworks/control/controller Control::host=127.0.0.1 Control::host_port=65531/tcp Control::cmd=configuration_update
+# @TEST-EXEC: btest-bg-run controllee  BROPATH=$BROPATH:.. bro -Bbroker %INPUT frameworks/control/controllee Broker::default_port=$BROKER_PORT
+# @TEST-EXEC: btest-bg-run controller  BROPATH=$BROPATH:.. bro -Bbroker %INPUT test-redef frameworks/control/controller Control::host=127.0.0.1 Control::host_port=$BROKER_PORT Control::cmd=configuration_update
 # @TEST-EXEC: btest-bg-wait 10
 # @TEST-EXEC: btest-diff controllee/.stdout
 
diff --git a/testing/btest/scripts/base/frameworks/control/id_value.bro b/testing/btest/scripts/base/frameworks/control/id_value.bro
index 13cf1c5548..2528b28c25 100644
--- a/testing/btest/scripts/base/frameworks/control/id_value.bro
+++ b/testing/btest/scripts/base/frameworks/control/id_value.bro
@@ -1,7 +1,7 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 #
-# @TEST-EXEC: btest-bg-run controllee  BROPATH=$BROPATH:.. bro %INPUT only-for-controllee frameworks/control/controllee Broker::default_port=65532/tcp
-# @TEST-EXEC: btest-bg-run controller  BROPATH=$BROPATH:.. bro %INPUT frameworks/control/controller Control::host=127.0.0.1 Control::host_port=65532/tcp Control::cmd=id_value Control::arg=test_var
+# @TEST-EXEC: btest-bg-run controllee  BROPATH=$BROPATH:.. bro %INPUT only-for-controllee frameworks/control/controllee Broker::default_port=$BROKER_PORT
+# @TEST-EXEC: btest-bg-run controller  BROPATH=$BROPATH:.. bro %INPUT frameworks/control/controller Control::host=127.0.0.1 Control::host_port=$BROKER_PORT Control::cmd=id_value Control::arg=test_var
 # @TEST-EXEC: btest-bg-wait -k 10
 # @TEST-EXEC: btest-diff controller/.stdout
 
diff --git a/testing/btest/scripts/base/frameworks/control/shutdown.bro b/testing/btest/scripts/base/frameworks/control/shutdown.bro
index cec965974a..a8089bf08a 100644
--- a/testing/btest/scripts/base/frameworks/control/shutdown.bro
+++ b/testing/btest/scripts/base/frameworks/control/shutdown.bro
@@ -1,6 +1,6 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 #
-# @TEST-EXEC: btest-bg-run controllee BROPATH=$BROPATH:.. bro %INPUT frameworks/control/controllee Broker::default_port=65530/tcp
-# @TEST-EXEC: btest-bg-run controller BROPATH=$BROPATH:.. bro %INPUT frameworks/control/controller Control::host=127.0.0.1 Control::host_port=65530/tcp Control::cmd=shutdown
+# @TEST-EXEC: btest-bg-run controllee BROPATH=$BROPATH:.. bro %INPUT frameworks/control/controllee Broker::default_port=$BROKER_PORT
+# @TEST-EXEC: btest-bg-run controller BROPATH=$BROPATH:.. bro %INPUT frameworks/control/controller Control::host=127.0.0.1 Control::host_port=$BROKER_PORT Control::cmd=shutdown
 # @TEST-EXEC: btest-bg-wait 10
 
diff --git a/testing/btest/scripts/base/frameworks/intel/cluster-transparency-with-proxy.bro b/testing/btest/scripts/base/frameworks/intel/cluster-transparency-with-proxy.bro
index bf6ed644ed..b81cac9bac 100644
--- a/testing/btest/scripts/base/frameworks/intel/cluster-transparency-with-proxy.bro
+++ b/testing/btest/scripts/base/frameworks/intel/cluster-transparency-with-proxy.bro
@@ -1,4 +1,7 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
+# @TEST-PORT: BROKER_PORT4
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run proxy-1  BROPATH=$BROPATH:.. CLUSTER_NODE=proxy-1 bro %INPUT
@@ -12,10 +15,10 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1"],
-	["proxy-1"]  = [$node_type=Cluster::PROXY,  $ip=127.0.0.1, $p=37762/tcp, $manager="manager-1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1"],
+	["proxy-1"]  = [$node_type=Cluster::PROXY,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT4")), $manager="manager-1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/intel/cluster-transparency.bro b/testing/btest/scripts/base/frameworks/intel/cluster-transparency.bro
index 62aabf6888..5362886cd7 100644
--- a/testing/btest/scripts/base/frameworks/intel/cluster-transparency.bro
+++ b/testing/btest/scripts/base/frameworks/intel/cluster-transparency.bro
@@ -1,4 +1,6 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run worker-1  BROPATH=$BROPATH:.. CLUSTER_NODE=worker-1 bro %INPUT
@@ -11,9 +13,9 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/intel/read-file-dist-cluster.bro b/testing/btest/scripts/base/frameworks/intel/read-file-dist-cluster.bro
index be1a526f1c..a4becfb2b3 100644
--- a/testing/btest/scripts/base/frameworks/intel/read-file-dist-cluster.bro
+++ b/testing/btest/scripts/base/frameworks/intel/read-file-dist-cluster.bro
@@ -1,4 +1,6 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run worker-1  BROPATH=$BROPATH:.. CLUSTER_NODE=worker-1 bro %INPUT
@@ -11,9 +13,9 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/intel/remove-item-cluster.bro b/testing/btest/scripts/base/frameworks/intel/remove-item-cluster.bro
index 6cc0fbdea0..5241231e1f 100644
--- a/testing/btest/scripts/base/frameworks/intel/remove-item-cluster.bro
+++ b/testing/btest/scripts/base/frameworks/intel/remove-item-cluster.bro
@@ -1,4 +1,5 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run worker-1  BROPATH=$BROPATH:.. CLUSTER_NODE=worker-1 bro %INPUT
@@ -9,8 +10,8 @@
 
 # @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1"],
 };
 # @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/logging/field-extension-cluster-error.bro b/testing/btest/scripts/base/frameworks/logging/field-extension-cluster-error.bro
index 57dca60afc..dd30ad4c6f 100644
--- a/testing/btest/scripts/base/frameworks/logging/field-extension-cluster-error.bro
+++ b/testing/btest/scripts/base/frameworks/logging/field-extension-cluster-error.bro
@@ -1,4 +1,5 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
 #
 # @TEST-EXEC: btest-bg-run manager-1 "cp ../cluster-layout.bro . && CLUSTER_NODE=manager-1 bro %INPUT"
 # @TEST-EXEC: btest-bg-run worker-1  "cp ../cluster-layout.bro . && CLUSTER_NODE=worker-1 bro --pseudo-realtime -C -r $TRACES/wikipedia.trace %INPUT"
@@ -10,8 +11,8 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1", $interface="eth0"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/logging/field-extension-cluster.bro b/testing/btest/scripts/base/frameworks/logging/field-extension-cluster.bro
index 066c1983e7..d38b5b744b 100644
--- a/testing/btest/scripts/base/frameworks/logging/field-extension-cluster.bro
+++ b/testing/btest/scripts/base/frameworks/logging/field-extension-cluster.bro
@@ -1,4 +1,5 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
 #
 # @TEST-EXEC: btest-bg-run manager-1 "cp ../cluster-layout.bro . && CLUSTER_NODE=manager-1 bro %INPUT"
 # @TEST-EXEC: btest-bg-run worker-1  "cp ../cluster-layout.bro . && CLUSTER_NODE=worker-1 bro --pseudo-realtime -C -r $TRACES/wikipedia.trace %INPUT"
@@ -8,8 +9,8 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1", $interface="eth0"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/netcontrol/acld-hook.bro b/testing/btest/scripts/base/frameworks/netcontrol/acld-hook.bro
index a0ce9c44d6..9e0db8531a 100644
--- a/testing/btest/scripts/base/frameworks/netcontrol/acld-hook.bro
+++ b/testing/btest/scripts/base/frameworks/netcontrol/acld-hook.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 # @TEST-EXEC: btest-bg-run recv "bro -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -b -r $TRACES/tls/ecdhe.pcap --pseudo-realtime ../send.bro >send.out"
 
@@ -21,7 +21,7 @@ event bro_init()
 
 event NetControl::init()
 	{
-	local netcontrol_acld = NetControl::create_acld(NetControl::AcldConfig($acld_host=127.0.0.1, $acld_port=Broker::default_port, $acld_topic="bro/event/netcontroltest"));
+	local netcontrol_acld = NetControl::create_acld(NetControl::AcldConfig($acld_host=127.0.0.1, $acld_port=to_port(getenv("BROKER_PORT")), $acld_topic="bro/event/netcontroltest"));
 	NetControl::activate(netcontrol_acld, 0);
 	}
 
@@ -35,7 +35,7 @@ event NetControl::init_done()
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
 	{
-	print "Broker peer added", endpoint$network;
+	print "Broker peer added", endpoint$network$address, endpoint$network$bound_port == to_port(getenv("BROKER_PORT"));
 	have_peer = T;
 
 	if ( did_init && have_peer )
@@ -104,7 +104,7 @@ event die()
 event bro_init()
 	{
 	Broker::subscribe("bro/event/netcontroltest");
-	Broker::listen("127.0.0.1");
+	Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
diff --git a/testing/btest/scripts/base/frameworks/netcontrol/acld.bro b/testing/btest/scripts/base/frameworks/netcontrol/acld.bro
index 7593790013..243e5e9b7c 100644
--- a/testing/btest/scripts/base/frameworks/netcontrol/acld.bro
+++ b/testing/btest/scripts/base/frameworks/netcontrol/acld.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 # @TEST-EXEC: btest-bg-run recv "bro -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -b -r $TRACES/tls/ecdhe.pcap --pseudo-realtime ../send.bro >send.out"
 
@@ -22,13 +22,13 @@ event bro_init()
 
 event NetControl::init()
 	{
-	local netcontrol_acld = NetControl::create_acld(NetControl::AcldConfig($acld_host=127.0.0.1, $acld_port=Broker::default_port, $acld_topic="bro/event/netcontroltest"));
+	local netcontrol_acld = NetControl::create_acld(NetControl::AcldConfig($acld_host=127.0.0.1, $acld_port=to_port(getenv("BROKER_PORT")), $acld_topic="bro/event/netcontroltest"));
 	NetControl::activate(netcontrol_acld, 0);
 	}
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
 	{
-	print "Broker peer added", endpoint$network;
+	print "Broker peer added", endpoint$network$address, endpoint$network$bound_port == to_port(getenv("BROKER_PORT"));
 	have_peer = T;
 
 	if ( did_init && have_peer )
@@ -109,7 +109,7 @@ event die()
 event bro_init()
 	{
 	Broker::subscribe("bro/event/netcontroltest");
-	Broker::listen("127.0.0.1");
+	Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
diff --git a/testing/btest/scripts/base/frameworks/netcontrol/basic-cluster.bro b/testing/btest/scripts/base/frameworks/netcontrol/basic-cluster.bro
index 0193e780d4..50c04433ad 100644
--- a/testing/btest/scripts/base/frameworks/netcontrol/basic-cluster.bro
+++ b/testing/btest/scripts/base/frameworks/netcontrol/basic-cluster.bro
@@ -1,4 +1,6 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
 #
 # @TEST-EXEC: btest-bg-run manager-1 "cp ../cluster-layout.bro . && CLUSTER_NODE=manager-1 bro %INPUT"
 # @TEST-EXEC: btest-bg-run worker-1  "cp ../cluster-layout.bro . && CLUSTER_NODE=worker-1 bro --pseudo-realtime -C -r $TRACES/tls/ecdhe.pcap %INPUT"
@@ -12,9 +14,9 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth0"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1", $interface="eth0"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1", $interface="eth0"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/netcontrol/broker.bro b/testing/btest/scripts/base/frameworks/netcontrol/broker.bro
index 9e8bb65476..4d232c3325 100644
--- a/testing/btest/scripts/base/frameworks/netcontrol/broker.bro
+++ b/testing/btest/scripts/base/frameworks/netcontrol/broker.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 # @TEST-EXEC: btest-bg-run recv "bro -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -b -r $TRACES/smtp.trace --pseudo-realtime ../send.bro >send.out"
 
@@ -22,7 +22,7 @@ event bro_init()
 
 event NetControl::init()
 	{
-	local netcontrol_broker = NetControl::create_broker(NetControl::BrokerConfig($host=127.0.0.1, $bport=Broker::default_port, $topic="bro/event/netcontroltest"), T);
+	local netcontrol_broker = NetControl::create_broker(NetControl::BrokerConfig($host=127.0.0.1, $bport=to_port(getenv("BROKER_PORT")), $topic="bro/event/netcontroltest"), T);
 	NetControl::activate(netcontrol_broker, 0);
 	}
 
@@ -36,7 +36,7 @@ event NetControl::init_done()
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
 	{
-	print "Broker peer added", endpoint$network;
+	print "Broker peer added", endpoint$network$address, endpoint$network$bound_port == to_port(getenv("BROKER_PORT"));
 	have_peer = T;
 
 	if ( did_init && have_peer )
@@ -93,7 +93,7 @@ event die()
 event bro_init()
 	{
 	Broker::subscribe("bro/event/netcontroltest");
-	Broker::listen("127.0.0.1");
+	Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
diff --git a/testing/btest/scripts/base/frameworks/notice/cluster.bro b/testing/btest/scripts/base/frameworks/notice/cluster.bro
index 9e04764d68..69d1ac8364 100644
--- a/testing/btest/scripts/base/frameworks/notice/cluster.bro
+++ b/testing/btest/scripts/base/frameworks/notice/cluster.bro
@@ -1,4 +1,6 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run proxy-1   BROPATH=$BROPATH:.. CLUSTER_NODE=proxy-1 bro %INPUT
@@ -8,9 +10,9 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=27757/tcp],
-	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=27758/tcp, $manager="manager-1"],
-	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=27760/tcp, $manager="manager-1", $interface="eth0"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1"],
+	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1", $interface="eth0"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/notice/suppression-cluster.bro b/testing/btest/scripts/base/frameworks/notice/suppression-cluster.bro
index a201c5f976..e9b31e1756 100644
--- a/testing/btest/scripts/base/frameworks/notice/suppression-cluster.bro
+++ b/testing/btest/scripts/base/frameworks/notice/suppression-cluster.bro
@@ -1,4 +1,7 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
+# @TEST-PORT: BROKER_PORT4
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run proxy-1   BROPATH=$BROPATH:.. CLUSTER_NODE=proxy-1 bro %INPUT
@@ -9,10 +12,10 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=27757/tcp],
-	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=27758/tcp, $manager="manager-1"],
-	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=27760/tcp, $manager="manager-1"],
-	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=27761/tcp, $manager="manager-1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["proxy-1"] = [$node_type=Cluster::PROXY,     $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1"],
+	["worker-1"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1"],
+	["worker-2"] = [$node_type=Cluster::WORKER,   $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT4")), $manager="manager-1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/openflow/broker-basic.bro b/testing/btest/scripts/base/frameworks/openflow/broker-basic.bro
index 83f83c15b4..9d43089b93 100644
--- a/testing/btest/scripts/base/frameworks/openflow/broker-basic.bro
+++ b/testing/btest/scripts/base/frameworks/openflow/broker-basic.bro
@@ -1,4 +1,4 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT
 # @TEST-EXEC: btest-bg-run recv "bro -b ../recv.bro >recv.out"
 # @TEST-EXEC: btest-bg-run send "bro -b -r $TRACES/smtp.trace --pseudo-realtime ../send.bro >send.out"
 
@@ -18,12 +18,12 @@ global of_controller: OpenFlow::Controller;
 event bro_init()
 	{
 	suspend_processing();
-	of_controller = OpenFlow::broker_new("broker1", 127.0.0.1, Broker::default_port, "bro/openflow", 42);
+	of_controller = OpenFlow::broker_new("broker1", 127.0.0.1, to_port(getenv("BROKER_PORT")), "bro/openflow", 42);
 	}
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
 	{
-	print "Broker peer added", endpoint$network;
+	print "Broker peer added", endpoint$network$address, endpoint$network$bound_port == to_port(getenv("BROKER_PORT"));
 	}
 
 event Broker::peer_lost(endpoint: Broker::EndpointInfo, msg: string)
@@ -83,7 +83,7 @@ event die()
 event bro_init()
 	{
 	Broker::subscribe("bro/openflow");
-	Broker::listen("127.0.0.1");
+	Broker::listen("127.0.0.1", to_port(getenv("BROKER_PORT")));
 	}
 
 event Broker::peer_added(endpoint: Broker::EndpointInfo, msg: string)
diff --git a/testing/btest/scripts/base/frameworks/openflow/log-cluster.bro b/testing/btest/scripts/base/frameworks/openflow/log-cluster.bro
index 5742a49d1d..33f20f8ce5 100644
--- a/testing/btest/scripts/base/frameworks/openflow/log-cluster.bro
+++ b/testing/btest/scripts/base/frameworks/openflow/log-cluster.bro
@@ -1,4 +1,5 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
 #
 # @TEST-EXEC: btest-bg-run manager-1 "cp ../cluster-layout.bro . && CLUSTER_NODE=manager-1 bro %INPUT"
 # @TEST-EXEC: btest-bg-run worker-1  "cp ../cluster-layout.bro . && CLUSTER_NODE=worker-1 bro --pseudo-realtime -C -r $TRACES/smtp.trace %INPUT"
@@ -7,8 +8,8 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1", $interface="eth0"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/sumstats/basic-cluster.bro b/testing/btest/scripts/base/frameworks/sumstats/basic-cluster.bro
index 9f665ef960..8f4bd26ef1 100644
--- a/testing/btest/scripts/base/frameworks/sumstats/basic-cluster.bro
+++ b/testing/btest/scripts/base/frameworks/sumstats/basic-cluster.bro
@@ -1,4 +1,6 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run worker-1  BROPATH=$BROPATH:.. CLUSTER_NODE=worker-1 bro %INPUT
@@ -9,9 +11,9 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1", $interface="eth0"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/sumstats/cluster-intermediate-update.bro b/testing/btest/scripts/base/frameworks/sumstats/cluster-intermediate-update.bro
index 5d8bff1e03..949fcb3644 100644
--- a/testing/btest/scripts/base/frameworks/sumstats/cluster-intermediate-update.bro
+++ b/testing/btest/scripts/base/frameworks/sumstats/cluster-intermediate-update.bro
@@ -1,4 +1,6 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run worker-1  BROPATH=$BROPATH:.. CLUSTER_NODE=worker-1 bro %INPUT 
@@ -8,9 +10,9 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1", $interface="eth0"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/sumstats/on-demand-cluster.bro b/testing/btest/scripts/base/frameworks/sumstats/on-demand-cluster.bro
index 14027f95ad..bb429a52cb 100644
--- a/testing/btest/scripts/base/frameworks/sumstats/on-demand-cluster.bro
+++ b/testing/btest/scripts/base/frameworks/sumstats/on-demand-cluster.bro
@@ -1,4 +1,6 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run worker-1  BROPATH=$BROPATH:.. CLUSTER_NODE=worker-1 bro %INPUT
@@ -10,9 +12,9 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1", $interface="eth0"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/sumstats/sample-cluster.bro b/testing/btest/scripts/base/frameworks/sumstats/sample-cluster.bro
index 811cad3b96..227313635a 100644
--- a/testing/btest/scripts/base/frameworks/sumstats/sample-cluster.bro
+++ b/testing/btest/scripts/base/frameworks/sumstats/sample-cluster.bro
@@ -1,4 +1,6 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run worker-1  BROPATH=$BROPATH:.. CLUSTER_NODE=worker-1 bro %INPUT
@@ -8,9 +10,9 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1", $interface="eth0"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/base/frameworks/sumstats/topk-cluster.bro b/testing/btest/scripts/base/frameworks/sumstats/topk-cluster.bro
index 6f371ba815..8a3a9bcf1b 100644
--- a/testing/btest/scripts/base/frameworks/sumstats/topk-cluster.bro
+++ b/testing/btest/scripts/base/frameworks/sumstats/topk-cluster.bro
@@ -1,4 +1,6 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run worker-1  BROPATH=$BROPATH:.. CLUSTER_NODE=worker-1 bro %INPUT
@@ -9,9 +11,9 @@
 #
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1", $interface="eth0"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE
 
diff --git a/testing/btest/scripts/policy/misc/weird-stats-cluster.bro b/testing/btest/scripts/policy/misc/weird-stats-cluster.bro
index a0652ed05b..140bb3b006 100644
--- a/testing/btest/scripts/policy/misc/weird-stats-cluster.bro
+++ b/testing/btest/scripts/policy/misc/weird-stats-cluster.bro
@@ -1,4 +1,6 @@
-# @TEST-SERIALIZE: comm
+# @TEST-PORT: BROKER_PORT1
+# @TEST-PORT: BROKER_PORT2
+# @TEST-PORT: BROKER_PORT3
 #
 # @TEST-EXEC: btest-bg-run manager-1 BROPATH=$BROPATH:.. CLUSTER_NODE=manager-1 bro %INPUT
 # @TEST-EXEC: btest-bg-run worker-1  BROPATH=$BROPATH:.. CLUSTER_NODE=worker-1 bro %INPUT
@@ -9,9 +11,9 @@
 
 @TEST-START-FILE cluster-layout.bro
 redef Cluster::nodes = {
-	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=37757/tcp],
-	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37760/tcp, $manager="manager-1", $interface="eth0"],
-	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=37761/tcp, $manager="manager-1", $interface="eth1"],
+	["manager-1"] = [$node_type=Cluster::MANAGER, $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT1"))],
+	["worker-1"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT2")), $manager="manager-1", $interface="eth0"],
+	["worker-2"]  = [$node_type=Cluster::WORKER,  $ip=127.0.0.1, $p=to_port(getenv("BROKER_PORT3")), $manager="manager-1", $interface="eth1"],
 };
 @TEST-END-FILE