This tutorial explains how to change the hostname on Debian 10 Buster without restarting the system.
The hostname is set at the time when the Debian operating system is installed or if you are spinning up a virtual machine it is dynamically assigned to the instance at startup.
To be able to change the system hostname you need to be logged in as root or user with sudo privileges.
Display the Current Hostname
In Debian 10 and all other Linux distributions using
systemd, you can change and display the hostname of a given system. with the
To view the current system hostname, type
hostnamectl without any option:
The output will show the current system hostname, in this example that is
Static hostname: host.justla.me Icon name: computer-vm Chassis: vm Machine ID: 70a3f06298014fd9ac42e5dc1de1034a Boot ID: 1dc8b9af89a4426b99cb348f6d483757 Virtualization: oracle Operating System: Debian GNU/Linux 10 (buster) Kernel: Linux 4.19.0-5-amd64 Architecture: x86-64
Change the System Hostname
A hostname is a label that identifies a machine on the network. You shouldn’t set the same hostname on two different machines on a same network. It is recommended to use a fully-qualified domain name (
FQDN) as the system hostname.
There are two steps involved when changing the system hostname on Debian 10. First, set the new hostname using the
hostnamectl set-hostname command followed by the desired hostname and then update the
/etc/hosts file with the new hostname.
For example, to change the system hostname to
arya.example.com, you would do the following steps:
First set the new hostname by running:
sudo hostnamectl set-hostname arya.example.com
hostnamectl command does not produce output. On success, 0 is returned, a non-zero failure code otherwise.
Second, open the
/etc/hosts file and replace the old hostname with the new one./etc/hosts
127.0.0.1 localhost 127.0.0.1 arya.example.com arya # The following lines are desirable for IPv6 capable hosts ::1 localhost ip6-localhost ip6-loopback ff02::1 ip6-allnodes ff02::2 ip6-allrouters
Verify the Change
To verify that the hostname was successfully changed, once again use the
The new system hostname will be printed on the command line.
Static hostname: arya.example.com Icon name: computer-vm Chassis: vm Machine ID: 70a3f06298014fd9ac42e5dc1de1034a Boot ID: 1dc8b9af89a4426b99cb348f6d483757 Virtualization: oracle Operating System: Debian GNU/Linux 10 (buster) Kernel: Linux 4.19.0-5-amd64 Architecture: x86-64
Changing system hostname on Debian 10 Buster is an easy task, involving only two simple steps.
Feel free to leave a comment if you have any questions.