Hostname

A name is the identifier of your computer on the network. A hostname is the DNS name of a computer on a network. Hostnames can be used for locating computers on the network. For the computer to contact another computer by using a hostname, the hostname will either appear in the DNS server or in the hosts file. In a fully qualified domain name, such as computer1.

server.tech-faq.com, the hostname portion of the FQDN is computer1. The server.tech-faq.

com is known as the suffix. Together, the hostname (computer1) and the suffix (server.tech-faq.

com) reference a single specific resource on a TCP/IP network. The suffix is important for hostnames as it allows two identical hostnames to exist on the network without conflict. For example, computer1.server.tech-faq.

com can exist on the same network with computer1.workstation.tech-faq.

com. The suffix is used to differentiate between the two names. Characteristics of Hostnames Hostname are used in virtually all TCP/IP environments.

The following provides details of a hostname: ? A hostname is an alias that an administrator assigns to a computer to identify an IP host. ? The hostname is a maximum 255 character string. ? A single hostname can be assigned to a host.

Name resolution methods, such as the hosts file or DNS, can have multiple hostnames which will map to the IP address of the same host. For example, the host server.tech-faq.com could have entries in DNS for both server.

tech-faq.com and www.tech-faq.com.

Either name will resolve to the IP address of server.tech-faq.com. ? It is possible for one hostname to resolve to more than one IP address. For example, three identical web servers are all identified in DNS with the name www.

tech-faq.com. When a client attempts to connect to www.

tech-faq.com through a web browser, three IP addresses are returned from the DNS query. ? A hostname can be used in place of an IP address when using the `ping` utility or other TCP/IP utilities.

? To be of value for name resolution, a hostname and its corresponding IP address must be configured either in a DNS server or in a hosts file. ? The `hostname` utility displays the hostname that is assigned to your system. ? Although Windows 2003 and Windows XP uses the same hostname as NetBIOS name, the hostname does not need to match the NetBIOS computer name.

Sean Hinds writes on topics such as Hostname , TCP and UDP for The Tech FAQ.