How to Change Hostname on Centos

CentOS Hostnames

A CentOS hostname is a unique name that identifies a CentOS system on a network. It is used to identify the system when connecting to it over the network, and it is also used to identify the system in log files and other diagnostic information.

There are a few different types of hostnames that can be used on a CentOS system. The most common type is a simple hostname, which consists of a single word or phrase. For example, “server1” or “web-server” are both valid simple hostnames.

In addition to simple hostnames, CentOS systems can also use fully qualified domain names (FQDNs) as their hostnames. An FQDN consists of a hostname and a domain name, separated by a period. For example, “server1.example.com” is an FQDN. FQDNs are often used in enterprise environments to allow systems to be easily identified and accessed from anywhere on the network.

Why do I Need to Change the Hostname on CentOS

You may need to change the hostname of your CentOS system for a variety of reasons. For example, you may need to change the hostname to reflect the system’s new role or location within your network. Alternatively, you may need to change the hostname to resolve a conflict with another system on the network.

In general, it is a good idea to choose a descriptive and meaningful hostname for your CentOS system. This will make it easier to identify and manage the system, and it will also make it easier to troubleshoot any issues that may arise.

Overall, the hostname is an important aspect of any CentOS system, and it is worth taking the time to choose a suitable hostname that reflects the system’s role and purpose.

So here is how to change the hostname on CentOS:

1. Edit the file /etc/hostname using a text editor such as vi or nano. The hostname is stored in this file as a single line of text.
2. Replace the existing hostname with the new hostname you want to use. Save the file and exit the text editor.
3. Edit the file /etc/hosts using a text editor. This file maps hostnames to IP addresses.
4. Look for the line that contains the current hostname and replace it with the new hostname. Save the file and exit the text editor.
5. Run the hostname command with the new hostname as an argument to set the hostname for the current session:

hostname new_hostname

6. Reboot the system for the changes to take effect permanently.

Note: If you are using a system with a GUI, you may also be able to change the hostname by going to the settings menu and finding the option to change the hostname. However, this method may not update all the necessary configuration files and is not recommended.