Oracle Database Discussions

I want to know the command for changing the localhost name in Oracle 11g I am trying to install. The instruction in the user guide is:

1. Start a local terminal session, for example, an X terminal (xterm).
2. If you are not installing the software on the local system, then enter the
following command to enable the remote host to display X applications on the
local X server:
$ xhost fully_qualified_remote_host_name
For example:
$ xhost somehost.us.example.com


Now, the first and foremost thing is that I wasn't asked to give a new localhost name while installing the Linux OS. Hence, the command prompt I am getting on the Terminal is:

[oradba2@localhost ~]$

The question is, how would I fulfill the above instruction so that I could get the correct host name? How do I change this???

Thanks