systemd-networkd is inactive by default since ubuntu 23.10?

[cheng cheng]

In the Ubuntu-23.10-64-Desktop and Ubuntu-24.04-64-Desktop, I run the commands as below. Found the systemd-networkd is inactive by default. In the ubuntu 22.10 and ubuntu 22.04 the systemd-networkd is active by default. I want to ask if there were any changes made since 23.10?

root@sc2-10-243-22-106:~# systemctl status systemd-networkd
○ systemd-networkd.service - Network Configuration
     Loaded: loaded (/usr/lib/systemd/system/systemd-networkd.>
     Active: inactive (dead)
TriggeredBy: ○ systemd-networkd.socket
       Docs: man:systemd-networkd.service(8)
             man:org.freedesktop.network1(5)
   FD Store: 0 (limit: 512)

root@sc2-10-243-22-106:~# systemctl status NetworkManager
● NetworkManager.service - Network Manager
     Loaded: loaded (/usr/lib/systemd/system/NetworkManager.se>
     Active: active (running) since Thu 2024-05-23 02:21:52 UT>
       Docs: man:NetworkManager(8)
   Main PID: 1134 (NetworkManager)
      Tasks: 4 (limit: 4609)
     Memory: 16.6M (peak: 32.7M)
        CPU: 2.721s
     CGroup: /system.slice/NetworkManager.service
             └─1134 /usr/sbin/NetworkManager --no-daemon

root@sc2-10-243-22-106:~# netplan status
     Online state: online
    DNS Addresses: 127.0.0.53 (stub)
       DNS Search: nimbus.eng.vmware.com
                   eng.vmware.com
                   vmware.com

● 1: lo ethernet UNKNOWN/UP (unmanaged)
      MAC Address: 00:00:00:00:00:00
        Addresses: 127.0.0.1/8
                   ::1/128

● 2: eth0 ethernet UP (NetworkManager: eth0)
      MAC Address: 00:50:56:b2:ec:a2 (VMware)
        Addresses: 10.243.22.106/20 (dhcp)
                   2606:9680:2001:2:b7c5:7bc2:3df4:4a25/64
                   2606:9680:2001:2:250:56ff:feb2:eca2/64
                   fe80::250:56ff:feb2:eca2/64 (link)
    DNS Addresses: 10.166.1.1
                   10.166.1.2
                   10.142.7.2
       DNS Search: nimbus.eng.vmware.com
                   eng.vmware.com
                   vmware.com
           Routes: default via 10.243.31.254 from 10.243.22.106
metric 100 (dhcp)
                   10.243.16.0/20 from 10.243.22.106 metric 100
(link)
                   2606:9680:2001:2::/64 metric 256
                   fe80::/64 metric 256
                   default via fe80::50:56ff:fe56:4453 metric
1024 (ra)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Nick Rosbrook (enr0n)]

As far as I know, systemd-networkd has never been enabled by default for Desktop installations. It is enabled by default on Server installations.

[cheng cheng (chcheng)]

Hi Nick,

Got it. Thanks a lot for your reply.

Best Regards,
Cheng

[Pengpeng Sun (pengpengs)]

Hi Nick,

Thanks for the info! So for Desktop, it's always NetworkManager as Netplan renderer; and for Server, it's systemd-networkd.
Another question, what if there is no renderer set in Netplan Yaml file, can Netplan load network configuration correctly?

[Pengpeng Sun (pengpengs)]

For example:

network:
  version: 2
  ethernets:
    enp3s0:
      dhcp4: true

[Danilo Egea Gondolfo (danilogondolfo)]

If no renderer is set anywhere in your YAMLs it will default to networkd.

[cheng cheng (chcheng)]

Hi Danilo,

Thanks for your reply.
In the Desktop version vm, as the systemd-networkd is disactive, when no renderer is set anywhere in the YAMLs, will it change to use Network Manager for the network configuration during "netplan apply"?

I tested on the ubuntu 23.10 Desktop vm, no render is set, the yaml file is as below:
  network:
  version: 2
  ethernets:
    eth0:
      dhcp4: yes
      dhcp4-overrides:
        use-dns: true
      dhcp6: yes
      dhcp6-overrides:
        use-dns: true

 Run the 'netplan apply' command, journalctl | grep netplan, it shows as below, does it mean it uses Network Manager at this configuration?

May 31 02:08:47 sc2-10-186-22-84 NetworkManager[852]: <info> [1717121327.8018] policy: auto-activating connection 'netplan-eth0' (626dd384-8b3d-3690-9511-192b2c79b3fd)
May 31 02:08:47 sc2-10-186-22-84 NetworkManager[852]: <info> [1717121327.8046] device (eth0): Activation: starting connection 'netplan-eth0' (626dd384-8b3d-3690-9511-192b2c79b3fd)
May 31 02:08:47 sc2-10-186-22-84 NetworkManager[852]: <info> [1717121327.8687] policy: set 'netplan-eth0' (eth0) as default for IPv4 routing and DNS

[cheng cheng (chcheng)]

Hi Ubuntu expert,

May I ask how can one differentiate whether an OS is a desktop or a server within the OS itself?
Can the presence of "/etc/netplan/01-network-manager-all.yaml" be used to differentiate a desktop environment?

Best Regards,
Cheng

[Lukas Märdian (slyon)]

More recently the Desktop enablement configuration moved to /usr/lib/netplan/00-network-manager-all.yaml

[Lukas Märdian (slyon)]

To differentiate an Ubuntu server system from an Ubuntu desktop system you should check with seeds/meta-package you have installed.

e.g.:
$ dpkg -l | grep "ubuntu-desktop-minimal" # or "ubuntu-server-minimal"

This is generated through the Ubuntu seeds and could be the authoritative way to check the type of system you're using.

PS: I'm closing this bug as "Invalid", as stated in comment #2 networkd is only enabled on Ubuntu server systems, NetworkManager only on Ubuntu desktop systems (by default), so I guess we're seeing the expeted behavior here.

Please comment & re-open if you feel otherwise.