How to change hostname of the linux machine

Host name is the name or label which is assigned to your computer that is used to identify and communicate. Usually you can choose your hostname while installation of operating system. If you take a server you may get machine with pre labeled hostname. It is always possible to change the hostname.

Note: You need root or sudo access to change the hostname of the machine.

There are different ways to changes the hostname of the computer. you  canchoose one of them. There is a volatile way and not volatile way. If you want change host name of the computer permanently you need to write your hostname in couple of files. If you want to change instantly (temporarily) you can change using couple of commands, but this change is volatile you will loose your hostname after reboot.

Using command hostname

Now, we will see  the way to change hostname instantly. This is not a persistent change. You will loose after reboot

The command hostname without arguments will display the current hostname of the system

Where you can give qualified hostname in the place of lintel.in. If you are using desktop linux(ubuntu) you can observer your change on (new session)shell, ie, user@hostname

Using sysctl

sysctl is the command that we use to configure kernel parameter at runtime. We can change hostname using this command as well. You can query the hostname using sysctl  as

To change hostname,

Changes made using either way are volatile. To make permanent change. Follow the below steps.

Edit hostname file

You have to edit the file /etc/hostname to make persistent change. This file contains only the hostname. To update hostname,

Including the above change you may need to edit /etc/hosts file. Change the 127.0.0.1   old_hostname  section. Replace old hostname with new hostname if you find.

it could be something like

Restart the machine to get your changes applied. You can combine both ways to get new hostname now and then after reboot.

Using hostnamectl

The linux distributions are also providing the command called hostnamectl to manage and set the hostname.

hostamectl with out any arguments will give the system hostname and other misc details

Check hostname

Set the hostname using hostnamectl

Chaging hostname using nmcli

Oh yeah, you can change the hostname using command nmcli as well. This command can be used to set the static hostname.

Query the hostname

Change the hostname