How to Change Hostname in CentOS/RHEL/OEL
Step1) Open the file /etc/sysconfig/network in vi editor and modify HOSTNAME to FQDN (test1.abs.com) [root@jagan1 oracle]# cat /etc/sysconfig/network NETWORKING=yes HOSTNAME=test1.abs.com [root@jagan1 oracle]# Step2) Change the hostname in /etc/hosts file Example: 192.168.72.128 test1.abs.com test1 [root@jagan1 oracle]# cat /etc/hosts 127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4 ::1 localhost localhost.localdomain localhost6 localhost6.localdomain6 192.168.72.128 test1.abs.com test1 [root@jagan1 oracle]# step3) Run Hostname [root@jagan1 oracle]# hostname test1.abs.com step4) Restart networking [root@jagan1 oracle]# /etc/init.d/network restart Shutting down loopback interface: [ OK ] Bringing up loopback interface: ...