Hostname was changed on the command prompt
 

Hi..I m having a problem on hostname on RedHad enterprise 4, I m not sure of the reason, one day the host name on the command prompt has changed to be root@dhcppc0:~ although at the time, I didn't try to work on dhcp (I m still in learning phase, & sometimes I make trials utilizing my few resources just to practise like making DNS using IP alias). Any way, I checked /etc/sysconfig/network & /etc/hosts & the host name in both is the old one: localhost@localdomain localhost.I tried to change them, but in vain!! I found similar problems but not an answer,can anybody help??Please provide me with reasons & solution, not just solution.
Thank you all.

It sounds like your network config is set to allow the DHCP server to assign a host name when it receives an IP address. This will take presidence over the host you set in sysconfig. You should be able to set the network card config not to allow DHCP to set the host name.