RedHat have their own ideas about how a machine should be configured. These are generally quite good, but obviously leads to 'local knowledge' required.
Most machine configuration happens in /etc/rc.d (or similar), and RedHat use a style that allows them to reconfigure machines from their scripts. Linux-FT from UNIFIX also has it's own scripts and parameter file mechanism, but RedHat's is clearer.
Slackware gets the hostname from /etc/HOSTNAME, RedHat gets it from the following shall script, and only keeps it in HOSTNAME for other apps to find.
NETWORKING=yes HOSTNAME=trix.dircon.co.uk DOMAINNAME=lan67 GATEWAY=192.168.67.254 GATEWAYDEV=eth0
DEVICE=eth0 IPADDR=192.168.67.1 NETMASK=255.255.255.0 NETWORK=192.168.67.0 BROADCAST=192.168.67.255 ONBOOT=yes
There are probably others, consult the RedHat manuals.