diff --git a/test/suites/add.sh b/test/suites/add.sh
index aeb1dc069..2ad5d299d 100644
--- a/test/suites/add.sh
+++ b/test/suites/add.sh
@@ -193,7 +193,6 @@ test_add_interactive() {
   export SETUP_ZFS="yes"
   export ZFS_FILTER="lxd_disk1"
   export ZFS_WIPE="yes"
-  export OVN_UNDERLAY_NETWORK="no"
   microcloud_interactive | lxc exec micro01 -- sh -c "microcloud add > out"
   lxc exec micro01 -- tail -1 out | grep "MicroCloud is ready" -q
 
@@ -211,7 +210,6 @@ test_add_interactive() {
   export SETUP_ZFS="no"
   export SETUP_CEPH="no"
   export SETUP_OVN="no"
-  export OVN_UNDERLAY_NETWORK="no"
 
   lxc exec micro04 -- snap disable microcloud
   microcloud_interactive | lxc exec micro01 -- sh -c "microcloud init > out"
diff --git a/test/suites/basic.sh b/test/suites/basic.sh
index 5fc36cf50..01d4142c7 100644
--- a/test/suites/basic.sh
+++ b/test/suites/basic.sh
@@ -696,7 +696,9 @@ _test_case() {
     export LOOKUP_IFACE="enp5s0" # filter string for the lookup interface table.
     export LIMIT_SUBNET="yes" # (yes/no) input for limiting lookup of systems to the above subnet.
     export CEPH_CLUSTER_NETWORK="${microcloud_internal_net_addr}"
-    export OVN_UNDERLAY_NETWORK="no"
+    if [ "${num_ifaces}" -gt 1 ] ; then
+      export OVN_UNDERLAY_NETWORK="no"
+    fi
 
     export EXPECT_PEERS="$((num_systems - 1))"