-n option. On a Linux system, you can also use
--nodename in lieu of -n, but
--nodename won't work on OS X. If the host name has not been set,
you will see localhost.localdomain displayed.
$ uname --nodename localhost.localdomain
You can also use the hostname command on a Linux or OS X system to show or set the host name. To show the host name, issue the command without any parameters
$ hostname localhost.localdomain
On some versions of Linux, e.g., CentOS and Ubuntu, you can also view the host name using the sysctl command; it won't work on OS X, however.
To set the host name, issue the command hostname new_name
from the root account or using sudo where new_name is the name
you wish to give the system. E.g.:
[root@localhost ~]# hostname localhost.localdomain [root@localhost ~]# hostname moonpoint [root@localhost ~]# hostname moonpoint [root@localhost ~]# uname -n moonpoint [root@localhost ~]# sysctl kernel.hostname kernel.hostname = moonpoint [root@localhost ~]#
The sysctl command can
also be used to set the host name on systems where sysctl kernel.hostname
works using sysctl kernel.hostname=new_name.
However, you will only be changing the "transient" host name by that
method. If you reboot, the commands will return the value they returned
before. If you issue the
hostnamectl command with the status argument, it will
show you whether you have a permanent or transient change to the host name.
# hostnamectl status
Static hostname: localhost.localdomain
Icon name: computer-vm
Chassis: vm
Machine ID: 72863e389b584a4dab36fae7f3bffda2
Boot ID: b9c1755c17d24493a177efc679fc9774
Virtualization: kvm
Operating System: CentOS Linux 7 (Core)
CPE OS Name: cpe:/o:centos:centos:7
Kernel: Linux 4.4.0-x86_64-linode63
Architecture: x86_64
[root@localhost ~]# hostname moonpoint
[root@localhost ~]# hostnamectl status
Static hostname: localhost.localdomain
Transient hostname: moonpoint
Icon name: computer-vm
Chassis: vm
Machine ID: 72863e389b584a4dab36fae7f3bffda2
Boot ID: b9c1755c17d24493a177efc679fc9774
Virtualization: kvm
Operating System: CentOS Linux 7 (Core)
CPE OS Name: cpe:/o:centos:centos:7
Kernel: Linux 4.4.0-x86_64-linode63
Architecture: x86_64
[root@localhost ~]#In the above example, you can see that after I issued the command
hostname moonpoint to change the host name to moonpoint,
hostnamectl status is now reporting "Transient hostname:
moonpoint", whereas previously it displayed "Static hostname:
localhost.localdomain". I can use the hostnamectl set-hostname
command to make the change permanent, so that it persists across a
reboot. E.g., as shown below, when I issue the command hostnamectl
set-hostname moonpoint, I see that the hostnamectl status
command shows the new name as "Static hostname".
[root@localhost ~]# hostnamectl set-hostname moonpoint
[root@localhost ~]# hostnamectl status
Static hostname: moonpoint
Icon name: computer-vm
Chassis: vm
Machine ID: 72863e389b584a4dab36fae7f3bffda2
Boot ID: b9c1755c17d24493a177efc679fc9774
Virtualization: kvm
Operating System: CentOS Linux 7 (Core)
CPE OS Name: cpe:/o:centos:centos:7
Kernel: Linux 4.4.0-x86_64-linode63
Architecture: x86_64
[root@localhost ~]#And I see the new value in
/etc/hostname, where
the host name is stored on CentOS and Ubuntu Linux systems, but not on OS X
systems, has been changed. If I just update the name with hostname
new_name or sysctl kernel.hostname=new_name,
I would not see the name changed in /etc/hostname. And, if I
reboot the system, I see the prompt change from "root@localhost" before
the reboot to "root@moonpoint" after the reboot when I log in as root.
Before:
[root@localhost ~]# reboot
After:
[root@moonpoint ~]#
If I changed the name with the hostname command, the prompt
did not change.
If you wish to permanently change the host name on an Apple OS X system,
use the command sudo scutil --set HostName new_name.