Change the Host Name and IP address of ubuntu

Under terminal, enter:
Gedit/etc/hostname (in the root permission environment)

Sudo gedit/etc/hostname (in a non-root environment)

Change the host name. Save and exit!

Modify IP Address

Modify IP Address: su enters the root permission Environment
Command to modify the IP address to: ifconfig eth1 192.168.1.100

Add

Su enters the root permission Environment
CD/etc
VI hosts
192.168.1.100 master
192.168.1.101 node1
192.168.1.102 node2

How do we delete a blank line in Vim?
It must be used in the previous row, or SHIFT + J. The effect is to merge the next row with a space, which is useful when writing a program.