Use hostnamectl which is a command-line client to systemd-hostnamed service
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[root@localhost sysconfig]# hostnamectl status
Static hostname: localhost.localdomain
Icon name: computer-vm
Chassis: vm
Machine ID: 12289ebafa0e47dea5171eee463b29aa
Boot ID: e370b31606ac4f41a6df3b96498ac107
Virtualization: kvm
Operating System: Oracle Linux Server 7.8
CPE OS Name: cpe:/o:oracle:linux:7:8:server
Kernel: Linux 3.10.0-1127.el7.x86_64
Architecture: x86-64
Set hostname:
============
[root@localhost sysconfig]# hostnamectl set-hostname oraerptest19c.com
[root@localhost sysconfig]#
Re-Login terminal session:
===================
[root@localhost sysconfig]# hostnamectl status
Static hostname: oraerptest19c.com
Icon name: computer-vm
Chassis: vm
Machine ID: 12289ebafa0e47dea5171eee463b29aa
Boot ID: e370b31606ac4f41a6df3b96498ac107
Virtualization: kvm
Operating System: Oracle Linux Server 7.8
CPE OS Name: cpe:/o:oracle:linux:7:8:server
Kernel: Linux 3.10.0-1127.el7.x86_64
Architecture: x86-64
[root@localhost sysconfig]# nmcli general hostname
oraerptest19c.com
[root@localhost sysconfig]# hostname
oraerptest19c.com
[root@localhost sysconfig]# nmcli general hostname oraerptest19c.com
[root@localhost sysconfig]# systemctl restart systemd-hostnamed
[root@localhost sysconfig]#
[root@localhost sysconfig]#
[root@localhost sysconfig]# hostname
oraerptest19c.com
[root@localhost sysconfig]#
[root@localhost sysconfig]# cat /etc/hostname
oraerptest19c.com
