Questions[openvswitch](server)

I've two OVS bridges which they are connected to the 3rd v-switch using patch(es).

    Bridge br1
        Port br1
            Interface br1
                type: internal
        Port br1-ext
            Interface br1-ext
                type: patch
                options: {peer=ext-br1}
        Port veth573b5f8a
            Interface veth573b5f8a
    Bridge br2
        Port br2
            Interface br2
                type: internal
        Port vethe3fada17
            Interface vethe3fada17
        Port br2-ext
            Interface br2-ext
                type: patch
                options: {peer=ext-br2}
    Bridge ext
        Port physnet1
            Interface physnet1
        Port ext-br1
            Interface ext-br1
                type: patch
                options: {peer=br1-ext}
        Port ext
            Interface ext
                type: internal
        Port ext-br2
            Interface ext-br2
                type: patch
                options: {peer=br2-ext}

There's a DHCP server over physnet1. I need to isolate L2 traffic between these v-switches but allow DHCP traffic from physnet1. How i can achieve that?

Note: There's N v-switches IRL.

Is there any command-line tool for the OVN Cluster Health check? Or each of its components? and a command or commands which gives stats about the cluster.

For example, without a functional test, I want to know if everything works properly in our OVN Cluster which has deployed with Kolla-Ansible.

All OVSDBs and OVN-NB-DBs and OVN-SB-DBs are healthy or not?, all Daemons are healthy or not?

I have seen that in virtual networking, guest VMs/containers can be connected with host and internet either by using kernel bridges(linux) or Virtual Switches.

Example - Bridges

docker uses linux kernel bridges to connect the guest containers to host and internet. Even, VMWare/VirtualBox allows to use bridge networking to connect the guest VM's with the host and internet. Example - Virtual Switches

VMWare ESX uses virtual switches to connect VM's with host and internet. Microsoft Hyper-V uses virtual switches to connect VM's with host and internet. So, I started to wonder what's the difference between these two (bridges and virtual switches) and which approach is better than the other.

(please feel free to edit the question to expand or make the question more meaningful.)

Here's my situation: I'm running CentOS 7 with Openvswitch and Libvirt/Qemu. My domains are configured to use the virtualport type openvswitch, so when I start a VM it creates a port in the ovs bridge. Nothing too complicated.

My problem is if I reboot the hypervisor, things don't seem to shut down in the correct order and I get stale OVS ports when the machine boots back up.

a7c1e36d-26b5-43d8-a422-452b013c4009
    Bridge "ovsbr0"
        Port "vnet1"
            tag: 46
            Interface "vnet1"
                error: "could not open network device vnet1 (No such device)"
        Port "vnet0"
            tag: 41
            Interface "vnet0"
                error: "could not open network device vnet0 (No such device)"
        Port "ovsbr0"
            Interface "ovsbr0"
                type: internal
        Port "bond0"
            Interface "bond0"
    ovs_version: "2.5.1"

I can kind of replicate this if I stop the openvswitch service, shut down the VMs and then start openvswitch again. Has anybody else seen this? If I start the VMs back up after this point the ovs ports are overwritten with non-stale ones, but I'd like to fix the actual issue here. Libvirt also segfaults when this problem happens during the reboot.

I'd like to say its as easy as modifying my systemd files to make sure the order is correct, but unfortunately openvswitch ships with init scripts for CentOS still, so the systemd files are autogenerated and I can't override the "After" parameter with a drop-in or anything (at least, it hasn't worked for me).

Anything, even an idea of something new to try would be great! Thanks in advance!

Is it possible to depatch a virtual switch; And is there any point to doing so on a virtual switch?