systemd-networkd-wait-online.service Failed to start Wait for Network to be Configured with bridge

[Johan Ehnberg]

The following simple netplan config results in a 2-minut unneccessary delay on boot. Everything works like it should in the end. The bridge has no interfaces due to a regression in Ubuntu migrating to netplan (see https://bugs.launchpad.net/ubuntu/+source/netplan.io/+bug/1779341).

ubuntu@molnix3:~$ cat /etc/netplan/01-netcfg.yaml
# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
  version: 2
  renderer: networkd
  ethernets:
    enp4s0:
      dhcp4: yes
      dhcp6: yes

ubuntu@molnix3:~$ cat /etc/netplan/br1.yaml
network:
  version: 2
  bridges:
    br1:
      addresses: [10.1.0.9/16]
      interfaces: []

ubuntu@molnix3:~$ cat /usr/lib/networkd-dispatcher/routable.d/tap0
#!/bin/sh
set -e
 if [ "$IFACE" = tap0 ]; then
  brctl addif br1 tap0
  ip link set tap0 promisc on
  ifmetric tap0 5
fi

ubuntu@molnix3:~$ journalctl -u systemd-networkd-wait-online.service -b
-- Logs begin at Thu 2018-06-28 10:07:29 UTC, end at Fri 2018-06-29 14:09:18 UTC. --
Jun 29 13:58:16 molnix3 systemd[1]: Starting Wait for Network to be Configured...
Jun 29 13:58:16 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:16 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:16 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:16 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:16 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:16 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:17 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:17 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:17 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:17 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:18 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:18 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:19 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:20 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:20 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 13:58:21 molnix3 systemd-networkd-wait-online[1468]: ignoring: lo
Jun 29 14:00:16 molnix3 systemd-networkd-wait-online[1468]: Event loop failed: Connection timed out
Jun 29 14:00:16 molnix3 systemd[1]: systemd-networkd-wait-online.service: Main process exited, code=exited, status=1/FAILURE
Jun 29 14:00:16 molnix3 systemd[1]: systemd-networkd-wait-online.service: Failed with result 'exit-code'.
Jun 29 14:00:16 molnix3 systemd[1]: Failed to start Wait for Network to be Configured.

ubuntu@molnix3:~$ /lib/systemd/systemd-networkd-wait-online
managing: br1
managing: enp4s0
ignoring: lo

ubuntu@molnix3:~$ networkctl
IDX LINK TYPE OPERATIONAL SETUP
  1 lo loopback carrier unmanaged
  2 enp4s0 ether routable configured
  3 br1 ether routable configured
  4 tap0 ether routable unmanaged

4 links listed.

[Launchpad Janitor (janitor)]

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

[Kees Bakker (keestux)]

My setup is a little bit different, but the problem is the same. I have a bridge device for LXD. This is an extra bridge for testing purpose.

root@rapper:~# cat /etc/netplan/91-test-bridges.yaml
network:
  version: 2
  renderer: networkd
  bridges:
    # the key name is the name for virtual (created) interfaces;
    # no ‘match’ or ‘set-name’ attributes are allowed.
    testbr0:
      addresses:
      - 10.82.0.1/24
      # gateway4: 192.168.178.1

At startup there are no containers using this bridge, and that causes the
2 minute timeout of systemd-networkd-wait-online

root@rapper:~# networkctl
IDX LINK TYPE OPERATIONAL SETUP
  1 lo loopback carrier unmanaged
  2 enp2s0 ether carrier configured
  3 testbr0 ether no-carrier configuring
  4 br0 ether routable configured

root@rapper:~# /lib/systemd/systemd-networkd-wait-online --timeout=20 --interface testbr0
ignoring: lo
Event loop failed: Connection timed out

I couldn't find a way to skip my test bridge for this online check, and
still keep it controlled by networkd.

[Dan Streetman (ddstreet)]

please reopen if this is still an issue