How to change the hostname on Linux

This post was originally published on go2linux.org on March 20, 2009. The domain is no longer mine, but I am the original author. I am republishing it here on garron.me with corrections and improvements.

Introduction

The hostname is the name that identifies your machine on a network. On modern Linux systems (Ubuntu 16.04+, Debian 8+, Fedora, CentOS 7+), the right tool to change it is hostnamectl, part of systemd.

The modern way: hostnamectl

View current hostname:

hostnamectl

Output:

 Static hostname: oldname
       Icon name: computer-server
         Chassis: server
      Machine ID: ...
         Boot ID: ...
Operating System: Ubuntu 24.04 LTS
          Kernel: Linux 6.8.0
    Architecture: x86-64

Set a new static hostname:

sudo hostnamectl set-hostname newname

The change takes effect immediately — no reboot needed.

Types of hostname

hostnamectl manages three types:

| Type | Description | Command | |---|---|---| | static | Stored in /etc/hostname, persists across reboots | hostnamectl set-hostname name | | transient | Temporary, set by DHCP or mDNS, lost on reboot | hostnamectl set-hostname name --transient | | pretty | Human-readable, may include spaces and special characters | hostnamectl set-hostname "My Server" --pretty |

For most purposes you only need to change the static hostname.

Update /etc/hosts

After changing the hostname, update /etc/hosts so the system can resolve its own name:

sudo nano /etc/hosts

Find the line with the old hostname and replace it:

127.0.1.1   newname

Without this step, some applications (like sudo) may show a warning about being unable to resolve the hostname.

Verify the change

hostname
hostnamectl status

The traditional method (non-systemd systems)

On older systems without systemd, the hostname is set in two places:

1. Edit /etc/hostname:

sudo nano /etc/hostname

Replace the content with the new name (just the hostname, no domain):

newname

2. Apply without rebooting:

sudo hostname newname

Or on Debian-based systems:

sudo /etc/init.d/hostname.sh start

The change will be permanent after the next reboot even without that last step, since /etc/hostname is read at boot.