netplan can not rename device names

[Thomas Aichinger]

I use Ubuntu 17.10 Server 64bit with latest updates. (Fresh installation)

apt-cache policy netplan
netplan:
  Installed: (none)
  Candidate: 1.10.1-5
  Version table:
     1.10.1-5 500
        500 http://at.archive.ubuntu.com/ubuntu artful/universe amd64 Packages

 apt-cache policy ifupdown
ifupdown:
  Installed: 0.8.16ubuntu2
  Candidate: 0.8.16ubuntu2
  Version table:
 *** 0.8.16ubuntu2 500
        500 http://at.archive.ubuntu.com/ubuntu artful/main amd64 Packages
        100 /var/lib/dpkg/status

systemd-networkd is installed and used
Network-Manager is not installed.
/etc/network/interfaces is untouched after installation

Netplan does not set device name configured in /etc/netplan/01-netcfg.yaml

Here my .yaml

network:
  version: 2
  renderer: networkd
  ethernets:
    lan:
      match:
        macaddress: 00:12:34:56:29:e8
      set-name: lan
      dhcp4: false
      dhcp6: false
      accept-ra: false
      addresses:
        - 10.10.0.48/24
        - 1701:5740:5000:3301::48/64

I had to switch back to predictable device names like "eth0" in /etc/default/grub with
GRUB_CMDLINE_LINUX_DEFAULT="net.ifnames=0 biosdevname=0" and update-grub.

After this change and reboot, the name is set properly but the network remains still unconfigured.
You have to login with console and type 'netplan apply' or 'systemctl restart systemd-networkd'.
This command will configure the network.

Funny thing about this behavior. If you reboot the system more often, out of 10 times one time network gets configured properly. I guess this is a timing issue.

'systemd-analize blame' shows what services are started at what time. I found out this difference.
With unconfigured network systemd-networkd is started at about 34ms
With configured network systemd-networkd is usually started at about 400ms

I played around a lot with timing in systemd-network.service but that did not change the thing.

[Mathieu Trudel-Lapierre (cyphermox)]

Moving this bug to the netplan project since the Ubuntu package got renamed from 'nplan' to 'netplan.io'.

[Daniel Axtens (daxtens)]

Hi,

I also hit this issue in LP: #1770082 - it turns out to be a systemd issue. I think the issues are duplicates.

Could you please test the latest netplan.io? It should be sufficient to fix your issue as it uses a more reliable renaming mechanism. If not, then we can debug further.

Regards,
Daniel

[Thomas Aichinger (taich)]

I have "Welcome to Ubuntu 18.04.1 LTS (GNU/Linux 4.15.0-29-generic x86_64)" with all upgrades.

I tried /etc/netplan/50-cloud-init.yaml

network:
    version: 2
    renderer: networkd
    ethernets:
        lan:
            match:
               macaddress: 00:50:56:a8:29:e8
            set-name: lan
            addresses:
            - 10.10.0.48/24
            - 1701:5740:5000:3301::48/64

It looks good now.

Regards
Thomas