HOSTNAME

NAME

SYNOPSIS

hostname [-v] [-F filename] [--file filename] [hostname]

domainname [-v] [-F filename] [--file filename] [name]

nodename [-v] [-F filename] [--file filename] [name]

hostname [-v] [-h] [--help] [-V] [--version]

dnsdomainname [-v]
nisdomainname [-v]
ypdomainname [-v]

DESCRIPTION

GET NAME

hostname will print the name of the system as returned by the gethostname(2) function.

domainname, nisdomainname, ypdomainname will print the name of the system as returned by the getdomainname(2) function. This is also known as the YP/NIS domain name of the system.

dnsdomainname will print the domain part of the FQDN (Fully Qualified Domain Name). The complete FQDN of the system is returned with hostname --fqdn.

The function gethostname(2) is used to get the hostname. When the hostname -a, -d, -f or -i is called will gethostbyname(3) be called. The difference in gethostname(2) and gethostbyname(3) is that gethostbyname(3) is network aware, so it consults /etc/nsswitch.conf and /etc/host.conf to decide whether to read information in /etc/sysconfig/network or /etc/hosts

To add another dimension to this, the hostname is also set when the network interface is brought up.

SET NAME

Note, that only the super-user can change the names.

It is not possible to set the FQDN or the DNS domain name with the dnsdomainname command (see THE FQDN below).

The host name is usually set once at system startup in /etc/rc.d/rc.inet1 or /etc/init.d/boot (normally by reading the contents of a file which contains the host name, e.g. /etc/hostname).

THE FQDN

Technically: The FQDN is the name gethostbyname(2) returns for the host name returned by gethostname(2). The DNS domain name is the part after the first dot.

Therefore it depends on the configuration (usually in /etc/host.conf) how you can change it. Usually (if the hosts file is parsed before DNS or NIS) you can change it in /etc/hosts.

OPTIONS

-a, --alias

Display the alias name of the host (if used).

-d, --domain

Display the name of the DNS domain. Don't use the command domainname to get the DNS domain name because it will show the NIS domain name and not the DNS domain name. Use dnsdomainname instead.

-F, --file filename

Read the host name from the specified file. Comments (lines starting with a `#') are ignored.

-f, --fqdn, --long

Display the FQDN (Fully Qualified Domain Name). A FQDN consists of a short host name and the DNS domain name. Unless you are using bind or NIS for host lookups you can change the FQDN and the DNS domain name (which is part of the FQDN) in the /etc/hosts file.

-h, --help

Print a usage message and exit.

-i, --ip-address

Display the IP address(es) of the host.

-s, --short

Display the short host name. This is the host name cut at the first dot.

-V, --version

Print version information on standard output and exit successfully.

-v, --verbose

Be verbose and tell what's going on.

-y, --yp, --nis

Display the NIS domain name. If a parameter is given (or --file name ) then root can also set a new NIS domain.

FILES

NOTE

AUTHOR