Setting a server’s hostname used to be as simple as running the ‘hostname’ command and adding a “HOSTNAME” entry in /etc/sysconfig/network. However things have changed quite a bit in RHEL7. Apparently, systemd now controls setting a server’s hostname. The ‘hostname‘ command no longer works to set your hostname, however the command is still available just to confuse you.

Now in RHEL 7 you use the command ‘hostnamectl‘. Below is an example of how it works.

Here I have logged into my a RHEL 7.1 VM. You can see that the system appears to have the hostname of node1.

[root@node1 ~]# hostname
node1

However upon further inspection, I find that this is not the case. Rather, the server has a static hostname of localhost.localdomain.

[root@node1 ~]# hostnamectl
Static hostname: localhost.localdomain
Transient hostname: node1
Icon name: computer-vm
Chassis: vm
Machine ID: 4c26a2a3101947bfa2ec7d9c16824ca4
Boot ID: f58707942bd1458da48680025b6f1a53
Virtualization: vmware
CPE OS Name: cpe:/o:redhat:enterprise_linux:7.1:GA:server
Kernel: Linux 3.10.0-229.el7.x86_64
Architecture: x86_64

So lets set the hostname permanently using ‘hostnamectl’.

[root@node1 ~]# hostnamectl set-hostname node1.packy.lab.localdomain

As you can see the hostname shows correct in the output of the ‘hostname’ command

[root@node1 ~]# hostname
node1.packy.lab.localdomain

… and in the output from ‘hostnamectl’

[root@node1 ~]# hostnamectl
Static hostname: node1.packy.lab.localdomain
Icon name: computer-vm
Chassis: vm
Machine ID: 4c26a2a3101947bfa2ec7d9c16824ca4
Boot ID: f58707942bd1458da48680025b6f1a53
Virtualization: vmware
Operating System: Employee SKU
CPE OS Name: cpe:/o:redhat:enterprise_linux:7.1:GA:server
Kernel: Linux 3.10.0-229.el7.x86_64
Architecture: x86_64