# hostnamectl set-hostname newhostname Then edit following files by replacing old hostname with new hostname if it exists in the files. +++++ # /etc/hosts # /etc/sysconfig/network # /home/interworx/iworx.ini # /var/qmail/control/locals # /var/qmail/control/me # /var/qmail/control/rcpthosts # /var/qmail/control/plusdomain # /var/qmail/control/smtpgreeting ++++ Restart the network and iworx services and reboot.