Ubuntu – Ubuntu Server 18.04 waiting for Network at startup although the network is ok

netplanserverwireless

I have fresh installation of Ubuntu Server 18.04. Until it is all set up and tested, I want it to be connected to both wired and wifi network.

My /etc/netplan directory contains two files:

01-netcfg.yaml

network:
  version: 2
  renderer: networkd
  wifis:
    wlp58s0:
      dhcp4: yes
      dhcp6: yes
      access-points:
        "MyNetworkName":
          password: "MyPassword"

50-cloud-init.yaml:

network:
  ethernets:
    eno1:
      addresses: []
      dhcp4: true
      optional: true
  version: 2

When the server boots up, it stays for 2 minutes on this message:

A start job is running for Wait for Network to be Configured.

While this message is displayed, the server can be pinged over the wired IP, but not over the wifi IP. It can be pinged over the wifi IP right after the 2 minutes of waiting have passed and user prompt is displayed on the connected display.

When I log on, ifconfig shows that both interfaces have initialized fine: both have received their IP addresses from the router, the server is reachable over the network at both IPs.

Here's the output of networkctl list command right after boot:

$ networkctl list
IDX LINK             TYPE               OPERATIONAL SETUP     
  1 lo               loopback           carrier     unmanaged 
  2 eno1             ether              routable    configured
  3 wlp58s0          wlan               routable    configured

The wifi router is about 2 meters close, the signal is very strong. Since I don't plan to restart the server too much, the problem of waiting is bearable. But I am afraid this could be a symptom of some network configuration that should be fixed before things get bad.

Best Answer

What if you add

  optional: yes

to your wifis/wlp58s0 configuration? I had a similar problem, but only when I booted without wired ethernet. The content of my /etc/netplan/01-netcfg.yaml (my only file in that dir) was

# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
  version: 2
  renderer: networkd
  ethernets:
    enp0s25:
      dhcp4: yes

When I appended

      optional: yes

the problem went away. The man 5 netplan page states that an optional device is not required for booting, and that the default is false.

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