Comment 15 for bug 1876884

What is your /proc/cmdline ?
-----------
$ cat /proc/cmdline
BOOT_IMAGE=/vmlinuz-5.4.0-29-generic root=/dev/mapper/vgubuntu-root ro quiet splash vt.handoff=7

Do you have `ip=` there? what is it?
-----------
No ip= option as you can see above.

It feels like you are booting with `ip=dhcp` set on the kernel commandline, when you do that, we bring netwokring up in the initramfs, and generate netplan.yaml for it.
-------------
I have an idea about this: The computers have their harddrive encrypted and therefore dropbear-initramfs is installed for remote unlocking. Because of that networking must be brought up during initramfs.

Can you please confirm if you have any /run/netplan/*.yaml files?
-------------------------
$ ls /run/netplan/*.yaml
/run/netplan/enp1s0.yaml

$ cat /run/netplan/enp1s0.yaml
network:
  version: 2
  renderer: networkd
  ethernets:
    enp1s0:
      dhcp4: true
      dhcp-identifier: mac
      critical: true
      nameservers:
        addresses: ["192.168.2.1"]
        search: ["fritz.box"]

Also can you please check what you have in /etc/cloud.cfg.d/* ? anything that has 'network:' key inside it?
----
The directory /etc/cloud.cfg.d/ does not exist.