None of the solutions I found seem to work and since I've been at it for days, I decided to give up and ask for help.

I have created an open vswitch called ovs-bridge with nmcli. I created ports and interfaces, and plugged in eno1. Everything works, I created a port with vlan tagging and a new interface gets an ip address from my dhcp server in that vlan.

Next step is I need kvm guests to plug into a vswitch port, with or without vlan tagging. For the life of me I cannot get this to work.

ovs-vsctl show:

```
4511e03b-87b5-44a2-a16f-dac79b43cbf7
    Bridge ovs-bridge
        Port ovs-p99
            Interface eno1
                type: system
        Port ovs-p1
            tag: 50
            Interface ovs-int-p1
                type: internal
        Port ovs-p0
            Interface ovs-int-p0
                type: internal

```

nmcli con show:

```
NAME           UUID                                  TYPE           DEVICE
ovs-int-p0     c6d2243f-8a96-4647-887a-d2cdfb8ae878  ovs-interface  ovs-int-p0
virbr0         ad67349b-3e2b-45ed-b66d-b148c7d01d4d  bridge         virbr0
ovs-bridge     dbb6960e-ac13-4452-b4c2-44782bbc54ac  ovs-bridge     ovs-bridge
ovs-int-p1     1af100a3-b08d-41bd-ab1f-a5c3059807f3  ovs-interface  ovs-int-p1
ovs-int-p99    3d64f617-4c9b-47a0-b48c-44380ea7d2bb  ethernet       eno1
ovs-p0         6e3a5415-8756-4069-a788-d661da078d46  ovs-port       ovs-p0
ovs-p1-vlan50  62f4cfe7-0317-4ca8-96f9-d37ac771b308  ovs-port       ovs-p1
ovs-p99        0a9c184c-0246-4cb1-a5bf-7c7b186b40e5  ovs-port       ovs-p99
wired-dhcp     760eda5d-f092-3ee0-998d-d923ff8bf5ca  ethernet       --

```

nmcli dev show:

```
DEVICE      TYPE           STATE                   CONNECTION
virbr0      bridge         connected (externally)  virbr0
ovs-int-p0  ovs-interface  connected               ovs-int-p0
eno1        ethernet       connected               ovs-int-p99
ovs-bridge  ovs-bridge     connected               ovs-bridge
ovs-int-p1  ovs-interface  connected               ovs-int-p1
ovs-p0      ovs-port       connected               ovs-p0
ovs-p1      ovs-port       connected               ovs-p1-vlan50
ovs-p99     ovs-port       connected               ovs-p99
lo          loopback       unmanaged               --
virbr0-nic  tun            unmanaged               --

```

I defined a network for libvirt to use:

```
<network>
  <name>ovs-network</name>
  <uuid>03026f19-5615-4d23-a8f0-adf1064a796a</uuid>
  <forward mode='bridge'/>
  <bridge name='ovs-bridge'/>
  <virtualport type='openvswitch'/>
  <portgroup name='untagged' default='yes'>
  </portgroup>
  <portgroup name='vlan50'>
    <vlan>
      <tag id='50'/>
    </vlan>
  </portgroup>
  <portgroup name='vlan60'>
    <vlan>
      <tag id='60'/>
    </vlan>
  </portgroup>
  <portgroup name='vlan-all'>
    <vlan trunk='yes'>
      <tag id='2'/>
      <tag id='3'/>
    </vlan>
  </portgroup>
</network>

```

The network is visible when I edit the guest in virt-manager. I defined the guest network as follows:

```
<interface type="network">
  <mac address="52:54:00:a6:dc:48"/>
  <source network="ovs-network" portgroup="untagged"/>
  <model type="virtio"/>
  <address type="pci" domain="0x0000" bus="0x07" slot="0x00" function="0x0"/>
</interface>

```

When I start the guest it comes back with the following:
virsh start fed32srv:

```
error: Failed to start domain fed32srv
error: Cannot get interface MTU on 'ovs-bridge': No such device

```

So I found a lot of information already:

* <https://serverfault.com/questions/680635/mtu-on-open-vswitch-bridge-port#81789>
* <https://docs.openvswitch.org/en/latest/faq/issues/>
* <https://stackoverflow.com/questions/48784098/issue-with-kvm-libvirt-and-linux-namespaces>

There are a million guides, most of which don't even work so I think a lot of that is outdated.

Anyway I tried setting MTU size on interfaces and the internal interface but that didn't help.
I restarted everything, even rebooted.

So back to the question, how can I setup kvm guests to plug into a vswitch port, with or without vlan tagging (on the ovs port)?

Ask if you need more information.

Thanks for the help!