diff --git a/lib/neutron_plugins/ovs_base b/lib/neutron_plugins/ovs_base
index f2a35dd340..fb3a154a00 100644
--- a/lib/neutron_plugins/ovs_base
+++ b/lib/neutron_plugins/ovs_base
@@ -68,9 +68,15 @@ function _neutron_ovs_base_install_ubuntu_dkms {
 function _neutron_ovs_base_install_agent_packages {
     if [ "$Q_BUILD_OVS_FROM_GIT" == "True" ]; then
         remove_ovs_packages
-        compile_ovs /usr/local /var
+        compile_ovs /usr/local
         load_conntrack_gre_module
-        start_new_ovs
+        # When OVN is the backend, ovn_agent:_start_ovs handles OVS
+        # lifecycle with its own DB and rundir. Starting OVS here would
+        # leave an orphaned ovs-vswitchd holding the kernel datapath,
+        # preventing the OVN-managed instance from creating bridges.
+        if ! is_service_enabled ovn-controller ovn-northd; then
+            start_new_ovs
+        fi
     else
         # Install deps
         install_package $(get_packages "openvswitch")
diff --git a/lib/neutron_plugins/ovs_source b/lib/neutron_plugins/ovs_source
index feb8f0acd0..e141b22368 100644
--- a/lib/neutron_plugins/ovs_source
+++ b/lib/neutron_plugins/ovs_source
@@ -128,7 +128,8 @@ function action_openvswitch {
 
 # start_new_ovs() - removes old ovs database, creates a new one and starts ovs
 function start_new_ovs {
-    sudo rm -f /etc/openvswitch/conf.db /etc/openvswitch/.conf.db~lock~
+    # DB path must match the compiled --prefix=/usr/local sysconfdir
+    sudo rm -f /usr/local/etc/openvswitch/conf.db /usr/local/etc/openvswitch/.conf.db~lock~
     sudo /usr/local/share/openvswitch/scripts/ovs-ctl start
 }