I currently maintain a host of machines in the RPM world from CentOS 5, CentOS 6, and now Fedora 20 (in preparation for CentOS 7). Being part of an upstream project that ships on many platforms, it is in my interest to make sure that all things “just work” on the myriad of platforms out there that we support.
In CentOS 6.5, changing a hostname is a process of editing /etc/sysconfig/network, making sure the /etc/hosts file is sensible and fixing it with the hostname command. Rackspace has a good support article on this.
This is the world before systemd. Now in Fedora 20, this muscle memory goes away in favour of using hostnamectl (docs from the excellent System Administrator’s Guide). Now all I have to do is: sudo hostnamectl set-hostname <newhostname>.
(and in other news, shutdown doesn’t understand the -f switch – invalid option code – this was to skip fsck on reboot – still valid in CentOS 5, accepted input in CentOS 6, but unlikely for CentOS 7.)