Update hostname and FQDN - Debian 8

Your system needs to have a fully qualified domain name (fqdn) in order to ……..

If you ever get such an error message from our server, then we need to set a Fully Qualified Domain Name (FQDN) on our Debian server.

To do so, we need to edit the file /etc/hosts and /etc/hostname.

Let’s assume our desired FQDN is foobar.example.com:

• Edit /etc/hosts and make sure these two lines are present.

    127.0.0.1	localhost
    127.0.1.1	foobar.example.com foobar
  

• Edit /etc/hostname content as follow:

    foobar
  

• Update hostname service:

    /etc/init.d/hostname.sh
  

Now check our updates

root@server:~# hostname
foobar.example.com


root@server:~# hostname --fqdn
foobar.example.com

root@server:~# hostname -f
foobar.example.com


root@server:~# dnsdomainname
example.com

Note: FQDN and the hosted domain names don’t have any relationship. We can use any domain name as our FQDN. Some random text (xxxx.xxxxx.xxx format) is always better.