[Bug 1833193] [NEW] systemd-network fails to apply static IPv4 when the static IP is the same as previously configured by DHCP

[Lars Erik Pedersen]

Public bug reported:

In bionic, running systemd 237-3ubuntu10.22 and netplan.io
0.97-0ubuntu1~18.04.1, systemd-networkd fails to configure an interface
with a static IPv4 address if the statically confiugred address is the
same as the interface already has gotten from DHCP.

This will cause the interface to loose its IP address when the DHCP
lease exires, even though you've told netplan to configure it as static.

I expect systemd-networkd to actually configure an IP address as static,
regardless of what address the interface has before from DHCP.

# lsb_release  -rd
Description:	Ubuntu 18.04.2 LTS
Release:	18.04

# apt-cache policy systemd
systemd:
  Installed: 237-3ubuntu10.22

# apt-cache policy netplan.io
netplan.io:
  Installed: 0.97-0ubuntu1~18.04.1

A paste of systemd-networkd's debug log when I run "netplan apply" and
the interface already has the static IP configured from DHCP.

It seems like upon a restart, systemd-networkd will allways add whatever
IP config it had before the service stopped, and then apply changes (if
any). Since my new config has the same IP as it already had, it does
nothing even though the new config has static configuration.

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

** Attachment added: "systemd-networkd debug log"
   https://bugs.launchpad.net/bugs/1833193/+attachment/5271319/+files/systemd-networkd-debug.txt

-- 
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/1833193

Title:
  systemd-network fails to apply static IPv4 when the static IP is the
  same as previously configured by DHCP

Status in systemd package in Ubuntu:
  New

Bug description:
  In bionic, running systemd 237-3ubuntu10.22 and netplan.io
  0.97-0ubuntu1~18.04.1, systemd-networkd fails to configure an
  interface with a static IPv4 address if the statically confiugred
  address is the same as the interface already has gotten from DHCP.

  This will cause the interface to loose its IP address when the DHCP
  lease exires, even though you've told netplan to configure it as
  static.

  I expect systemd-networkd to actually configure an IP address as
  static, regardless of what address the interface has before from DHCP.

  # lsb_release  -rd
  Description:	Ubuntu 18.04.2 LTS
  Release:	18.04

  # apt-cache policy systemd
  systemd:
    Installed: 237-3ubuntu10.22

  # apt-cache policy netplan.io
  netplan.io:
    Installed: 0.97-0ubuntu1~18.04.1

  A paste of systemd-networkd's debug log when I run "netplan apply" and
  the interface already has the static IP configured from DHCP.

  It seems like upon a restart, systemd-networkd will allways add
  whatever IP config it had before the service stopped, and then apply
  changes (if any). Since my new config has the same IP as it already
  had, it does nothing even though the new config has static
  configuration.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1833193/+subscriptions