Linux get host name

Best 5 commands to check HostName in Linux

A hostname (also known as a Computer Name) is a name which is given to a device (It could be a system, switch, router, etc) that is connected to the network, and is used to identify it over a network. There cannot be two systems with same host names within the same network.

The purpose of assigning names to IP addresses is to make them easier for people to remember. In reality, an IP address identifies a network interface associated with a device like a network card.

Refer the following articles on how to change a hostname in Linux:

By default, the hostname can be found in the terminal, but it only shows the first part when the hostname is large (each hostname usually has at least one numeric network address associated with it).

In this tutorial, we will show you how to check hostname using several ways in Linux.

• hostnamectl Command: hostnamectl command is controling the system hostname.
• nmcli Command: nmcli is a command-line tool for controlling NetworkManager.
• uname Command: Print certain system information.
• hostname: Show or set system host name.
• sysctl: sysctl command allows us to configure kernel parameters at runtime.

1) Checking HostName using hostnamectl command

hostnamectl may be used to query and change the system hostname and related settings. Run the hostnamectl command to view the system hostname as shown below:

$ hostnamectl or $ hostnamectl status Static hostname: daygeek-Y700 Icon name: computer-laptop Chassis: laptop Machine ID: 31bdeb7b83230a2025d43547368d75bc Boot ID: 267f264c448f000ea5aed47263c6de7f Operating System: Manjaro Linux Kernel: Linux 4.19.20-1-MANJARO Architecture: x86-64

2) Checking the Linux system hostname

Hostname is the program that is used to either set or display the current host, domain or node name of the system. These names are used by many of the networking programs to identify the machine. The domain name is also used by NIS/YP.

3) Checking HostName with uname command

uname (stands for unix name) is a utility that prints the system information like name, version and other details about the system, and the operating system running on it:

$ uname -a | awk '' CentOS.2daygeek.com

4) Checking HostName using nmcli command

nmcli is a command-line tool for controlling NetworkManager and reporting network status.

nmcli is used to create, display, edit, delete, activate, and deactivate network connections, as well as control and display network device status. Also, it allow us to view the hostname.

Use the following format to view the current hostname using nmcli :

$ nmcli general hostname daygeek-Y700

5) Checking HostName using sysctl command

‘sysctl’ is used to modify kernel parameters at runtime. The parameters available are those listed under /proc/sys/. Procfs is required for sysctl support in Linux. You can use sysctl to both read and write sysctl data.

$ sysctl kernel.hostname kernel.hostname = daygeek-Y700

Bonus Tips:

Alternatively, you can use the following commands to verify the hostname in Linux. These are additional methods but I rather recommend using the aforementioned five commands as they are most widely used.

• nmtui Command: nmtui is a text User Interface for controlling NetworkManager.
• /etc/hostname file: This file is containing the static system hostname.
• /etc/hosts: /etc/hosts file is an operating system file that maps hostnames to IP addresses.
• /etc/sysconfig/network: The /etc/sysconfig/network file specifies additional information that is valid to all network interfaces on the system.
• /proc/sys/kernel/hostname: The proc filesystem (procfs) is a special filesystem in Unix-like operating systems.

Method-1: Check HostName using /etc/hostname file

Alternatively, we can view the hostname by using the /etc/hostname file.

Check the current hostname using /etc/hostname file.

$ cat /etc/hostname daygeek-Y700

Method-2: Check HostName using /etc/hosts file

‘/etc/hosts’ file is an operating system file that maps hostnames to IP addresses before DNS can be referenced. It is a plain text file, one line per IP address. It’s a static table lookup for hostnames as shown below:

$ cat /etc/hosts | grep daygeek 127.0.1.1 daygeek-Y700

Method-3: Check HostName using ProcFS in Linux

The proc filesystem (procfs) is a special filesystem in Unix-like operating systems that presents information about processes and other system information.

It’s sometimes referred to as a process information pseudo-file system. It doesn’t contain ‘real’ files but runtime system information (e.g. system memory, devices mounted, hardware configuration, etc).

$ cat /proc/sys/kernel/hostname daygeek-Y700

Method-4: View HostName with nmtui

nmtui is a curses‐based TUI application for interacting with NetworkManager. When starting nmtui, the user is prompted to choose the activity to perform unless it was specified as the first argument.

Run the following command on terminal to launch the terminal user interface:

Method-5: Check HostName using /etc/sysconfig/network file

The ‘/etc/sysconfig/network’ file specifies additional information that is valid to all network interfaces on the system.

For RHEL/CentOS 6 systems only:

$ cat /etc/sysconfig/network | grep -i hostname HOSTNAME=CentOS.2daygeek.com

Wrapping Up

In this tutorial we’ve shown you ten commands to check the hostname in Linux.

If you found this article helpful, please do share with your friends and spread the knowledge. Please feel free to comment below if you have any queries/concerns. We will get back to you as soon as we can. Happy learning!

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Linux get host name

NAME

hostname - show or set the system's host name domainname - show or set the system's NIS/YP domain name ypdomainname - show or set the system's NIS/YP domain name nisdomainname - show or set the system's NIS/YP domain name dnsdomainname - show the system's DNS domain name

SYNOPSIS

hostname [-a|--alias] [-d|--domain] [-f|--fqdn|--long] [-A|--all-fqdns] [-i|--ip-address] [-I|--all-ip-addresses] [-s|--short] [-y|--yp|--nis] hostname [-b|--boot] [-F|--file filename] [hostname] hostname [-h|--help] [-V|--version] domainname [nisdomain] [-F file] ypdomainname [nisdomain] [-F file] nisdomainname [nisdomain] [-F file] dnsdomainname 

DESCRIPTION

Hostname is used to display the system's DNS name, and to display or set its hostname or NIS domain name. GET NAME When called without any arguments, the program displays the current names: hostname will print the name of the system as returned by the gethostname(2) function. domainname will print the NIS domainname of the system. domainname uses the gethostname(2) function, while ypdomainname and nisdomainname use the yp_get_default_domain(3). dnsdomainname will print the domain part of the FQDN (Fully Qualified Domain Name). The complete FQDN of the system is returned with hostname --fqdn (but see the warnings in section THE FQDN below). SET NAME When called with one argument or with the --file option, the commands set the host name or the NIS/YP domain name. hostname uses the sethostname(2) function, while all of the three domainname, ypdomainname and nisdomainname use setdomainname(2). Note, that this is effective only until the next reboot. Edit /etc/hostname for permanent change. 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/init.d/hostname.sh (normally by reading the contents of a file which contains the host name, e.g. /etc/hostname). THE FQDN The FQDN (Fully Qualified Domain Name) of the system is the name that the resolver(3) returns for the host name, such as, ursula.example.com. It is usually the hostname followed by the DNS domain name (the part after the first dot). You can check the FQDN using hostname --fqdn or the domain name using dnsdomainname. You cannot change the FQDN with hostname or dnsdomainname. The recommended method of setting the FQDN is to make the hostname be an alias for the fully qualified name using /etc/hosts, DNS, or NIS. For example, if the hostname was "ursula", one might have a line in /etc/hosts which reads 127.0.1.1 ursula.example.com ursula Technically: The FQDN is the name getaddrinfo(3) 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 of the resolver (usually in /etc/host.conf) how you can change it. Usually the hosts file is parsed before DNS or NIS, so it is most common to change the FQDN in /etc/hosts. If a machine has multiple network interfaces/addresses or is used in a mobile environment, then it may either have multiple FQDNs/domain names or none at all. Therefore avoid using hostname --fqdn, hostname --domain and dnsdomainname. hostname --ip-address is subject to the same limitations so it should be avoided as well.

OPTIONS

-a, --alias Display the alias name of the host (if used). This option is deprecated and should not be used anymore. -A, --all-fqdns Displays all FQDNs of the machine. This option enumerates all configured network addresses on all configured network interfaces, and translates them to DNS domain names. Addresses that cannot be translated (i.e. because they do not have an appropriate reverse IP entry) are skipped. Note that different addresses may resolve to the same name, therefore the output may contain duplicate entries. Do not make any assumptions about the order of the output. -b, --boot Always set a hostname; this allows the file specified by -F to be non-existant or empty, in which case the default hostname localhost will be used if none is yet set. -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. See the warnings in section THE FQDN above, and avoid using this option. -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. See the warnings in section THE FQDN above und use hostname --all- fqdns instead wherever possible. -F, --file filename Read the host name from the specified file. Comments (lines starting with a `#') are ignored. -i, --ip-address Display the network address(es) of the host name. Note that this works only if the host name can be resolved. Avoid using this option; use hostname --all-ip-addresses instead. -I, --all-ip-addresses Display all network addresses of the host. This option enumerates all configured addresses on all network interfaces. The loopback interface and IPv6 link-local addresses are omitted. Contrary to option -i, this option does not depend on name resolution. Do not make any assumptions about the order of the output. -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. -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. -h, --help Print a usage message and exit.

NOTES

FILES

/etc/hostname Historically this file was supposed to only contain the hostname and not the full canonical FQDN. Nowadays most software is able to cope with a full FQDN here. This file is read at boot time by the system initialization scripts to set the hostname. /etc/hosts Usually, this is where one sets the domain name by aliasing the host name to the FQDN.

AUTHORS

Peter Tobias, tobias@et-inf.fho-emden.de> Bernd Eckenfels, net-tools@lina.inka.de> (NIS and manpage). Michael Meskes, meskes@debian.org>

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