[Bug 1804478] [NEW] netplan dhcp interface with no default route causes causes systemd-networkd-wait-online to hang

[Mikko Korkalo]

Public bug reported:

root cause in systemd bug:
https://github.com/systemd/systemd/issues/3752

Environment:
Ubuntu 18.04 LTS amd64
systemd package version 237-3ubuntu10.9

How to trigger:
1. add netplan interface with dhcpv4 client enabled:
        enp0s8:
            addresses: []
            dhcp4: true
2. configure dhcp server to NOT give a default route, or any route for that matter
3. reboot
4. systemd-networkd-wait-online will block until dhcp renew is triggered
root at sensor1:~# /lib/systemd/systemd-networkd-wait-online --timeout=3
Event loop failed: Connection timed out
root at sensor1:~# /lib/systemd/systemd-networkd-wait-online --timeout=3 --ignore=enp0s8
managing: enp0s3
ignoring: lo
ignoring: enp0s8

How to fix:
Backport upstream changes from systemd (see related systemd ticket).

** Affects: systemd (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: systemd

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to systemd in Ubuntu.
https://bugs.launchpad.net/bugs/1804478

Title:
  netplan dhcp interface with no default route causes causes systemd-
  networkd-wait-online to hang

Status in systemd package in Ubuntu:
  New

Bug description:
  root cause in systemd bug:
  https://github.com/systemd/systemd/issues/3752

  Environment:
  Ubuntu 18.04 LTS amd64
  systemd package version 237-3ubuntu10.9

  How to trigger:
  1. add netplan interface with dhcpv4 client enabled:
          enp0s8:
              addresses: []
              dhcp4: true
  2. configure dhcp server to NOT give a default route, or any route for that matter
  3. reboot
  4. systemd-networkd-wait-online will block until dhcp renew is triggered
  root at sensor1:~# /lib/systemd/systemd-networkd-wait-online --timeout=3
  Event loop failed: Connection timed out
  root at sensor1:~# /lib/systemd/systemd-networkd-wait-online --timeout=3 --ignore=enp0s8
  managing: enp0s3
  ignoring: lo
  ignoring: enp0s8

  How to fix:
  Backport upstream changes from systemd (see related systemd ticket).

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1804478/+subscriptions