How to change Hostname on Oracle Solaris and Linux

Step # 1: Change Hostname

You need to update two files:

1. Linux Distribution specific file. Edit appropriate file as per your distribution as follows.
2. /etc/hosts

Redhat / CentOS / Fedora: Change Hostname

Edit /etc/sysconfig/network, enter:

vi /etc/sysconfig/network

Set HOSTNAME=newhost.example.com, enter:

HOSTNAME=server2.nixcraft.com

Save and close the file. Type the following command:

hostname server2.nixcraft.com
hostname

Now, proceed to step # 2.

Debian / Ubuntu: Change Hostname

Edit, /etc/hostname file, enter:

vi /etc/hostname

Delete old name and add new name:

server2.nixcraft.com

Save and close the file. Type the following command:

hostname server2.nixcraft.com
hostname

Now, proceed to step # 2.

Slackware: Change Hostname

Edit /etc/HOSTNAME, enter:

vi /etc/HOSTNAME

Delete old name and add new one:

server2.nixcraft.com

Save and close the file. Type the following command:

hostname server2.nixcraft.com
hostname

Now, proceed to step # 2.

Suse / OpenSuse: Change Hostname

Edit /etc/HOSTNAME, enter:
Delete old name and add new one:

server2.nixcraft.com

Save and close the file. Type the following command:

hostname server2.nixcraft.com
hostname

Now, proceed to step # 2.

Step #2: Update /etc/hosts

Now, you need to edit /etc/hosts file, enteR:

vi /etc/hosts

Change all old hostname with newer one.