Outputs of Options available in `hostname` command

1) `-a` Option in `hostname` command in Linux

Display all aliases of the host.

Syntax:

hostname -a

2) `-A` Option in `hostname` command in Linux

 Syntax:

hostname -A

3) `-b` Option in `hostname` command in Linux

 Syntax:

hostname -b

4) `-d` Option in `hostname` command in Linux

 Display the domain name of the host if any.

Syntax:

hostname -d

5) `-f` Option in `hostname` command in Linux 

Display the fully qualified domain name (FQDN) of the host.

 Syntax:

hostname -f

6) `-F` Option in `hostname` command in Linux

 This option is used to set the hostname specified in a file. Can be performed by the superuser(root) only. 

Syntax:

sudo hostname -F filename

7) `-i` Option in `hostname` command in Linux

 Display the IP address of the host

Syntax:

hostname -i

8) `-I` Option in `hostname` command in Linux 

 This option is used to get all IP (network) addresses. The option doesn’t depend on resolvability of hostname.

hostname -I

9) `-s` Option in `hostname` command in Linux 

Display the short hostname of the host.

 Syntax:

hostname -s

10) `-V` Option in `hostname` command in Linux

Display the version information about the hostname 

 Syntax:

hostname -V

11) How to set hostname in Linux 

Set the hostname of the system temporarily.

Syntax:

sudo hostname NEW_HOSTNAME

Replace NEW_HOSTNAME with the new hostname you want to set. (Here we have changed it to “w3wiki”)

Set the hostname of the system permanently.

To set the hostame of our system permanently we have to go inside “/etc/hostname” using text editor and change hostname to the hostname we want.

hostname command in Linux is used to obtain the DNS (Domain Name System) name and set the system’s hostname or NIS (Network Information System) domain name. A hostname is a name given to a computer and attached to the network. Its main purpose is to uniquely identify over a network.