diff --git a/ci/common/net-config-multinode-os-net-config.yaml b/ci/common/net-config-multinode-os-net-config.yaml
index 24545c3aa7..6e31088482 100644
--- a/ci/common/net-config-multinode-os-net-config.yaml
+++ b/ci/common/net-config-multinode-os-net-config.yaml
@@ -71,9 +71,16 @@ resources:
               let vni+=$subnode_index
               sed -i "s/vni/$vni/" /etc/os-net-config/config.json
               export interface_name="br-ex_$primary_private_ip"
-              # Until we are fully migrated to os-net-config we need to clean
-              # up the old bridge first created by devstack-gate
-              ovs-vsctl del-br br-ex
+
+              # Until we are fully migrated to os-net-config we need
+              # to clean up the old bridge first created by
+              # devstack-gate. However, if $interface_name is already
+              # present in `ovs-vsctl show`, assume our br-ex is
+              # already configured. (Mainly for upgrade job, to avoid
+              # deleting br-ex during upgrade.)
+              if ! ovs-vsctl show | grep $interface_name &> /dev/null; then
+                ovs-vsctl del-br br-ex
+              fi
             }
 
           -