change hostname on a linux machine -centos

I want to change my Linux hostname from Linux01 to Linux03

[root@Linux01 Desktop]# vi /etc/sysconfig/network

[root@Linux01 Desktop]# cat /etc/sysconfig/network
NETWORKING=yes
HOSTNAME=Linux03

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YOU MIGHT ALSO WANT TO CHECK THE /ETC/HOSTS FILE FOR IP SETTINGS
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RESTART THE SERVER NOW. AFTER REBOOT

[oracle@Linux03 Desktop]$ hostname
Linux03

[oracle@Linux03 Desktop]$