Setting the system's hostname is a simple matter of using the hostname command. If you are on a network, your hostname should be the full hostname of your machine, such as goober.norelco.com. If you are not on a network of any kind, you can choose an arbitrary host and domainname, such as loomer.vpizza.com, shoop.nowhere.edu, or floof.org.
When setting the hostname, the hostname must appear in the file /etc/hosts, which assigns an IP address to each host. Even if your machine is not on a network, you should include your own hostname in /etc/hosts.
For example, if you are not on a TCP/IP network, and your hostname is floof.org, simply include the following line in /etc/hosts:
This assigns your hostname, floof.org, to the loopback address 127.0.0.1 (used if you're not on a network). The localhost alias is also assigned to this address.
If you are on a TCP/IP network, however, your real IP address and hostname should appear in /etc/hosts. For example, if your hostname is goober.norelco.com, and your IP address is 128.253.154.32, add the following line to /etc/hosts:
If your hostname does not appear in /etc/hosts, you will not be able to set it.
To set your hostname, simply use the hostname command. For example, the command
sets the hostname to goober.norelco.com. In most cases, the hostname command is executed from one of the system startup files, such as /etc/rc or /etc/rc.local. Edit these two files and change the hostname command found there to set your own hostname; upon rebooting the system the hostname will be set to the new value.