Output of 'facter fqdn' is different from 'hostname -f'

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1

Problem:
Hi there.

Really enthousiast to test out the foreman.
Unfortunately i cannot install foreman on Debian : 10.11
the foreman-installer is in version : 3.1.0-1

when i do :

foreman-installer -i

i got

Output of 'facter fqdn' is different from 'hostname -f'

Make sure above command gives the same output. If needed, change the hostname permanently via the
'hostname' or 'hostnamectl set-hostname' command
and editing the appropriate configuration file.
(e.g. on Red Hat systems /etc/sysconfig/network,
on Debian based systems /etc/hostname).

If 'hostname -f' still returns an unexpected result, check /etc/hosts and put
the hostname entry in the correct order, for example:

  1.2.3.4 hostname.example.com hostname

The fully qualified hostname must be the first entry on the line
Your system does not meet configuration criteria

I tried thoses advices : Fixing foreman-installer "Forward DNS points to " errors - Puppeteers Oy

without success.

Also i tried many /etc/hosts and /etc/hostname settings without any succes .

Can someone give me a clue on how to properly setting up hostname to install correctly the foreman ?

Thank you very much.

Expected outcome:

Foreman and Proxy versions:

Foreman and Proxy plugin versions:

Distribution and version:

Debian 10.11
foreman-installler 3.1.0-1

Other relevant data:

2

Make sure above command gives the same output. If needed, change the hostname permanently via the ‘hostname’ or ‘hostnamectl set-hostname’ command and editing the appropriate configuration file.
(e.g. on Red Hat systems /etc/sysconfig/network, on Debian based systems /etc/hostname).

If ‘hostname -f’ still returns an unexpected result, check /etc/hosts and put the hostname entry in the correct order, for example:

1.2.3.4 hostname.example.com hostname

The fully qualified hostname must be the first entry on the line. Your system does not meet configuration criteria.