diff --git a/overlays/bird/ovs-config.sh b/overlays/bird/ovs-config.sh
new file mode 100755
index 0000000..86265c4
--- /dev/null
+++ b/overlays/bird/ovs-config.sh
@@ -0,0 +1,25 @@
+#!/bin/sh
+#
+# OVS configuration for the `bird` overlay
+
+LAB=${LAB:=0}
+for node in 0 1 2 3; do
+  for int in 0 1 2 3; do
+    ovs-vsctl set port vpp${LAB}-${node}-${int} vlan_mode=native-untagged
+  done
+done
+
+# Uplink is VLAN 10
+ovs-vsctl add port vpp${LAB}-0-0 tag 10
+
+# Link vpp${LAB}-0 <-> vpp${LAB}-1 in VLAN 20
+ovs-vsctl add port vpp${LAB}-0-1 tag 20
+ovs-vsctl add port vpp${LAB}-1-0 tag 20
+
+# Link vpp${LAB}-1 <-> vpp${LAB}-2 in VLAN 21
+ovs-vsctl add port vpp${LAB}-1-1 tag 21
+ovs-vsctl add port vpp${LAB}-2-0 tag 21
+
+# Link vpp${LAB}-2 <-> vpp${LAB}-3 in VLAN 22
+ovs-vsctl add port vpp${LAB}-2-1 tag 22
+ovs-vsctl add port vpp${LAB}-3-0 tag 22
diff --git a/overlays/default/ovs-config.sh b/overlays/default/ovs-config.sh
new file mode 120000
index 0000000..810b9d7
--- /dev/null
+++ b/overlays/default/ovs-config.sh
@@ -0,0 +1 @@
+../bird/ovs-config.sh
\ No newline at end of file