Comment 4 for bug 1940844

I checked it on the test node and here is what I found.
When job failed it was ovs 2.12 running:

$ sudo ovs-vsctl show
a05a7746-2638-49c9-8f3a-4c293fb6aff2
    Manager "ptcp:6640:127.0.0.1"
        is_connected: true
    Bridge br-ctlplane
        fail_mode: standalone
        Port br-ctlplane
            Interface br-ctlplane
                type: internal
    Bridge br-int
        fail_mode: secure
        Port br-int
            Interface br-int
                type: internal
    Bridge br-ex
        Port br-ex
            Interface br-ex
                type: internal
    ovs_version: "2.12.0"

and because of that there was no patch ports between bridges created and in that it was same bug as [CIX][BZ:1989974][osp17][rhel8][RHOS17][RHOS16.2]Multinode jobs are failing to ping the router ip address in os_tempest.

But there was already installed ovs 2.13:
sudo su bash-4.4# rpm -qa | grep openvswitch rdo-openvswitch-2.13-3.el8.noarch python3-rdo-openvswitch-2.13-3.el8.noarch openvswitch-selinux-extra-policy-1.0-28.el8.noarch python3-openvswitch2.13-2.13.0-122.el8.x86_64 network-scripts-openvswitch2.13-2.13.0-122.el8.x86_64 rdo-network-scripts-openvswitch-2.13-3.el8.noarch openvswitch2.13-2.13.0-122.el8.x86_64

So I decided to restart openvswitch on the node, and then all seemed to be configured properly:

bash-4.4# systemctl restart openvswitch
bash-4.4# ovs-vsctl show
a05a7746-2638-49c9-8f3a-4c293fb6aff2
    Manager "ptcp:6640:127.0.0.1"
        is_connected: true
    Bridge br-ctlplane
        fail_mode: standalone
        Port patch-provnet-eb568cc3-4ac1-43a2-9ca8-080bc5a44aca-to-br-int
            Interface patch-provnet-eb568cc3-4ac1-43a2-9ca8-080bc5a44aca-to-br-int
                type: patch
                options: {peer=patch-br-int-to-provnet-eb568cc3-4ac1-43a2-9ca8-080bc5a44aca}
        Port br-ctlplane
            Interface br-ctlplane
                type: internal
    Bridge br-int
        fail_mode: secure
        datapath_type: system
        Port br-int
            Interface br-int
                type: internal
        Port patch-br-int-to-provnet-eb568cc3-4ac1-43a2-9ca8-080bc5a44aca
            Interface patch-br-int-to-provnet-eb568cc3-4ac1-43a2-9ca8-080bc5a44aca
                type: patch
                options: {peer=patch-provnet-eb568cc3-4ac1-43a2-9ca8-080bc5a44aca-to-br-int}
    Bridge br-ex
        Port br-ex
            Interface br-ex
                type: internal
    ovs_version: "2.13.5"

So it seems that we should install ovs 2.13 instead of 2.12 at the beginning of the job or restart it after update of that package before tempest is run.