How to Change the Hostname of a Vultr Cloud Instance

Learn how to change the hostname on CentOS, Fedora, Ubuntu, Debian, FreeBSD, and Windows Server systems without reinstalling or losing data, while ensuring the new name persists across reboots and cloud-init resets.

A hostname is a name that is given to a system within a network to uniquely identify it among other devices. It serves as a human-readable label that simplifies communication, troubleshooting, and management. Instead of remembering IP addresses, administrators and users can reference machines using recognizable names like web01, db-server, or node1.example.com.

Hostname are important for:

DNS resolution
SSH access
Monitoring and logging

Changing the hostname is a common task when setting up new servers, applying naming conventions, or preparing systems for production environments.

Note

Changing the hostname using the Vultr Customer Portal triggers a full server reinstall because it uses cloud-init to set the hostname during provisioning. This process erases all data on the server, including the operating system and files.

Follow this guide to change the hostname on CentOS, Fedora, FreeBSD, Ubuntu, and Windows Server without reinstalling the server or losing any data.

Prerequisites

Before you begin, you need to:

Have access to a Linux server as a non-root user with sudo privileges.

Disable the Automatic Hostname Update

To make your hostname changes permanent, remove the hostname related directives from the /etc/cloud/cloud.cfg file. This prevents cloud-init from resetting the hostname on reboot.

Open the /etc/cloud/cloud.cfg file using an test editor.
console
```
$ sudo nano /etc/cloud/cloud.cfg
```
Locate the cloud_init_modules section and remove the following directives.
```
- set_hostname
- update_hostname
- update_etc_hosts
```
Save and close the file.

Change the hostname on CentOS and Fedora.

Follow the steps below to change the hostname on RHEL-based distros like CentOS or Fedora.

View the hostname of your server.
console
```
$ hostname
```
Your output should be similar to the one below:
```
my-hostname
```
Change the server hostname by running the following command.
console
```
$ sudo hostnamectl set-hostname my-new-hostname
```
Replace my-new-hostname with the new hostname you want to set.
Update the /etc/hosts file with the new hostname. Also if you have a DNS entry then the best practice is to update the name in this file as well.
console
```
$ sudo nano /etc/hosts
```
After updating, the file should be similar to the one below:
```
...
127.0.0.1 my-new-hostname my-new-hostname.example.com
127.0.0.1 localhost.localdomain localhost
...
```
Reboot the server to apply the changes.
console
```
$ sudo reboot
```
Verify that your hostname changes are reflected on the server.
console
```
$ hostnamectl
```
Output:
```
Static hostname: my-new-hostname
...
```
Verify that your hosts file changes is also reflected.
console
```
$ cat /etc/hosts
```
Your output should be similar to the one below:
```
...
127.0.1.1 my-new-hostname my-new-hostname.example.com
127.0.0.1 localhost
...


Change the hostname on Ubuntu oN  Debian
```
Follow the steps below to change the hostname on Ubuntu or other Debian-based distributions without reinstalling the system or losing any data.
1. View the hostname of your server.
  console
  
  $ hostname
  Your output should be similar to the one below:
```
my-hostname
```
2. Change the hostname using the hostnamectl command.
  console
  
  $ sudo hostnamectl set-hostname my-new-hostname
  Replace my-new-hostname with the new hostname you want to set.
3. Update the /etc/hosts file with the new hostname. Also if you have a DNS entry then the best practice is to update the name in this file as well.
  console
  
  $ sudo nano /etc/hosts
  After updating, the file should be similar to the one below:
```
...
127.0.1.1 my-new-hostname my-new-hostname.example.com
127.0.0.1 localhost
...
```
4. Reboot the server to apply the changes.
  console
  
  $ sudo reboot
5. After rebooting, verify that the hostname and hosts file changes are applied.
  console
  
  $ hostnamectl $ cat /etc/hosts
  The above commands should display your new hostname in both the system configuration and the /etc/hosts file, confirming that the changes are reflected and is persistent.
Change the hostname on FreeBSD
Follow the steps below to change the hostname on a FreeBSD system.
1. View the hostname of your server.
  console
  
  $ hostname
  Your output should be similar to the one below:
```
my-hostname
```
2. Edit the /etc/rc.conf file to update the server hostname.
  console
  
  $ sudo vim /etc/rc.conf
  Your updated configuration file should be similar to the one below:
```
hostname="my-new-hostname"
sshd_enable="YES"
...
```
  Replace my-new-hostname with the new hostname you want to set.
3. Update the /etc/hosts file to include the new hostname.
  console
  
  $ sudo vim /etc/hosts
  After updating, the file should be similar to the one below:
```
...
127.0.0.1 my-new-hostname my-new-hostname.example.com
::1       my-new-hostname
...
```
4. Reboot your system to apply the changes.
  console
  
  $ sudo reboot
5. After reboot, verify that your hostname and hosts related changes are reflected.
  console
  
  $ hostname $ cat /etc/hosts
  This above commands should display the new hostname and your hosts file with new changes.
Change the hostname on Windows Server
Follow the steps below to change the hostname on Windows Server using either PowerShell or the graphical interface.

Note

Before changing the hostname, ensure that no critical roles are already installed. Renaming a system with configured roles such as a domain controller or Exchange server can lead to conflicts. Always create a snapshot or backup before proceeding.

Change the Hostname Using PowerShell

Follow the steps below to change the Windows server hostname using Powershell.
1. Open the Windows PowerShell as an administrator.
2. View the Windows server hostname.
  pwsh
  
  PS C:\> $env:COMPUTERNAME
  Output:
```
MY-HOSTNAME
```
3. Change the Windows server hostname.
  pwsh
  
  PS C:\> Rename-Computer -NewName "MY-NEW-HOSTNAME" -Restart
  Replace MY-NEW-HOSTNAME with your desired hostname. The -Restart parameter restarts the server to apply the change.
4. After the system reboots, verify the hostname.
  pwsh
  
  PS C:\> $env:COMPUTERNAME
  Output:
```
MY-NEW-HOSTNAME
```
Change the Hostname Using the Windows GUI
1. Log in to your server using Remote Desktop (RDP).
2. Open File Explorer, right click This PC, and select Properties.
3. In the Properties window, go to the System section and open the About page.
4. Click the Rename this PC button.
5. Enter the new hostname and click Next.
6. Click Restart now to restart the server and44444 apply the changes.
Conclusion
In this guide, you changed the hostname across multiple operating systems without reinstalling your server or losing data. You updated the hostname configuration on CentOS, Fedora, FreeBSD, Ubuntu, and Windows Server using system-specific tools and disabled cloud-init to prevent overwrites. These steps ensured the changes persisted across reboots and followed best practices for system administration.

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