Comment 0 for bug 1879243

StarlingX 3.0 release

AIO duplex with 2 datanetworks: physnet0 is based on vlan and physnet1 on vxlan. controller-0 and controller-1 are identically speced: eno1 to oam, eno2 to data0 (physnet0), enp1s0f0 to mgmt0, and enp1s0f1 to data1 (physnet1). eno* are 1gbe when enp* are 10gbe, not that it matters.

interface for data1 set to MTU=9216, accelerated=True

datanetwork physnet0 vlan mtu 1500; physnet1 vxlan mtu 9050

```
controller-1:~$ OS_CLOUD=openstack_helm openstack network segment range list
| ID | Name | Default | Shared | Project ID | Network Type | Physical Network | Min ID | Max ID
| ... | physnet0-vlan-r1 | False | False | ... | vlan | physnet0 | 120 | 130
| .. | physnet1-vxlan-r1 | False | True | None | vxlan | None | 100 | 99999

controller-1:~$ OS_CLOUD=openstack_helm openstack network create --project betatest testnet
controller-1:~$ OS_CLOUD=openstack_helm openstack network show testnet | grep mtu
| mtu | 1450
```

The guest network testnet backed by vxlan, which is great. However, the mtu is messed up. I can modify the mtu manually or specify it when creating the network. Sadly, that is not possible in horizon and thus end users self servicing will end up with 1450.