Comment 8 for bug 1627641

This isn't reproducible in yakkety, but it does reproduce locally in a QEMU xenial instance (although a lot harder than on the infra, which is why I didn't see it at first). It seems systemd 229's systemd-networkd-wait-online has a bug that it does not actually wait for the interfaces to be fully configured. When it exits, the status is

● 412: eth42
       Link File: /lib/systemd/network/99-default.link
    Network File: /run/systemd/network/10-netplan-eth42.network
            Type: ether
           State: degraded (configured)
          Driver: veth
      HW Address: 0a:9b:04:93:f9:c0
             MTU: 1500
         Address: fe80::89b:4ff:fe93:f9c0
             DNS: 2600:0000:0000:0000:0000:0000:0000:0001

i. e. the interface is still being set up. I would not like to work around that in the tests, because if we are actually going to use networkd on xenial the integration with network-online.target must work.