ubuntu-20.04 ignores domain name setting from DHCP (option 15)

[Josef Wolf]

Hello,

With a default install of ubuntu-20.04. the dhcp-option 15 (domain part of
clients the FQDN) is ignored.

journalctl confirms that the dhcp server sends the domain name:

  Aug 04 16:22:03 h730 NetworkManager[1055]: <info>  [1628086923.4702] dhcp4 (wlp3s0): option domain_name          => 'wolf.lan'
  [ ... ]
  Aug 04 16:22:03 h730 NetworkManager[1055]: <info>  [1628086923.4703] dhcp4 (wlp3s0): option requested_domain_name => '1'
  
But the domain name is not set:

  jw at h730:~$ hostname -f
  h730
  jw at h730:~$

Any ideas?

-- 
Josef Wolf
jw at raven.inka.de