HowTo Set RHEL7 Hostname
Overview
This HowTo will provide some information about the different types of hostnames and how to set them in RHEL7 (Redhat 7 or CentOS 7) based machine. If you have built your new RHEL7 based machine and have now got a bit stuck over how to change the hostname from localhost.localdomain to what ever you want this is the how to for you.
Types Of Hostnames
There are three types of hostnames: Static, Pretty and Transient.
Static Hostname
The Static hostname is essentially the traditional hostname which is stored in the “/etc/hostname” file.
[user@server ~]$ cat /etc/hostname
server.example.com
Transient Hostname
The Transient hostname is a dynamic hostname which is maintained at a kernel level. It is initialized by the static hostname, but can be changed by DHCP and other network services.
Pretty Hostname
The Pretty hostname is a free form hostname for presentation to the user.
Set The Hostname
The hostname can be changed by editing the “/etc/hostname” file or with the hostnamectl command.
[root@server ~]# hostnamectl set-hostname server-test.example.com
This command will set all three hostnames at the same time, but all three can be set individually using the “-static”, “-transient” or “-pretty” flags.
Validate “/etc/hostname” has been updated
[root@server ~]# cat /etc/hostname
server-test.example.com
Hostname Information
You can see a bit of information with the hostnamectl command which is very useful. man hostnamectl
[root@server ~]# hostnamectl
Static hostname: server.domain.tld
Icon name: computer-vm
Chassis: vm
Machine ID: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Boot ID: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Virtualization: vmware
Operating System: CentOS Linux 7 (Core)
CPE OS Name: cpe:/o:centos:centos:7
Kernel: Linux 3.10.0-123.4.4.el7.x86_64
Architecture: x86_64