A hostname is what identifies a server. Most Windows Server users name their servers with the hostname consisting of two parts:
role part is the role installed on the server, followed by the number. For example,
dc01 if this is the first server that acts as a DC in this particular network. Then, Windows makes this an FQDN by putting the Active Directory domain as the
domain part. For example, if this is the third web server in this network, and the domain is
contoso.com, the hostname would be:
Note that changing the hostname on Windows Server may conflict with some installed roles. It is a good idea to change the hostname before installing roles on the server. If you decide to change the hostname on a Windows Server with roles installed, though, I recommend making a snapshot first. Therefore, if something breaks, you will be able to restore your server from that snapshot.