Public bug reported:
## Summary
On Ubuntu Server with desktop environment installed, a DHCP address assigned in
the initramfs stage (by dracut/systemd-networkd) persists after boot, even when
NetworkManager + Netplan are configured for static IP via `renderer:
NetworkManager`. The static configuration is ignored.
## Environment
- Ubuntu 26.04 LTS
- Kernel: 7.0.0-27-generic
- Interface: enp3s0 (Realtek RTL810xE)
- Stack: NetworkManager + Netplan (renderer: NetworkManager)
- Initramfs: dracut (residual config)
## Steps to Reproduce
1. Install Ubuntu Server 26.04
2. Install desktop: `sudo apt install ubuntu-desktop-minimal`
3. Configure static IP via Netplan (renderer: NetworkManager):
/etc/netplan/90-NM-*.yaml → addresses: [192.168.1.200/24], routes: [{to:
default, via: 192.168.1.1}]
4. (Optional trigger) ln -sf /run/systemd/network/zzzz-dracut-default.network
/etc/systemd/network/zzzz-dracut-default.network
5. Reboot
6. ip -4 a show enp3s0
## Expected
- enp3s0: 192.168.1.200/24, no "dynamic" flag
## Actual
- enp3s0: 192.168.1.210/24 scope global dynamic (DHCP)
- Static IP ignored
## Root Cause (preliminary)
- Dracut generates `/run/systemd/network/zzzz-dracut-default.network`
(DHCP=yes) in initramfs
- systemd-networkd in initramfs acquires DHCP lease before pivot to user space
- DHCP address remains in kernel state; NetworkManager fails to fully replace it
- Netplan validation warnings (deprecated `gateway4`) exacerbate — if netplan
generate fails, NM gets no static config at all
## Workaround
sudo ln -sf /dev/null /etc/systemd/network/zzzz-dracut-default.network
sudo update-initramfs -u -k all
(plus fix Netplan: remove gateway4, correct addresses)
## Affects
Also affects: dracut, network-manager, systemd (initramfs networkd)
Suggest subscribing Ubuntu Foundations Team.
## Attachment
Collected system state: [attach ubuntu-network-bug-report-*.tar.gz]
** Affects: netplan
Importance: Undecided
Status: New
** Affects: netplan.io (Ubuntu)
Importance: Undecided
Status: New
** Tags: dracut initramfs network-race server-desktop
** Attachment added: "ubuntu-network-bug-report-20260626-084139.tar.gz"
https://bugs.launchpad.net/bugs/2158368/+attachment/5979088/+files/ubuntu-network-bug-report-20260626-084139.tar.gz
** Tags added: dracut initramfs network-race server-desktop
** Also affects: netplan
Importance: Undecided
Status: New
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https://bugs.launchpad.net/bugs/2158368
Title:
[SRU] DHCP address from initramfs (dracut) persists on Server+desktop
with NetworkManager renderer
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