# For Windows :
# Open your text editor in Administrator mode.
# In the text editor, open C:\Windows\System32\drivers\etc\hosts.
# Add the IP Address and hostname.
#Example: opm.server.com

# Save the changes.
# For Linux :
# Open terminal.
# Use the nano command line text editor or a different one you have available to open the hosts file. The command with nano is as follows (the command will require your Linux user password)   

sudo nano /etc/hosts

# Add the appropriate changes in the hosts file.
# Example: opm.server.com

# Use the Control and 'X' key combination to save the changes.

The hosts file (also referred to as etc\hosts) is a text file used by operating systems including windows to map IP addresses to host names/domain names. This file acts as a local DNS service for your local machine and it overrides the mappings from the DNS server to which your machine is connected over the network.


Before the advent of DNS, the host table was the only way of resolving hostnames on the fledgling Internet.