initial_server_setup.sh

#!/bin/bash
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#Note         : Use this script at your risk
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#Script Name  : initial_server_setup.sh                                                                                           
#Description  : setup a non root user with name "ubuntu" 
##            : and give superuser priviliges along with a
##            : basic firewall setup                                                                               
#Args         : 1) server public IP Address,
##            : 2) path to .pem file
#Usage        : bash initial_server_setup.sh
#Author       : Sri Teja                                                
#Email        : asriteja77712<at>gmail<dot>com
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## initial server setup with ubuntu 18.04
echo "Starting..."

## Enter your server public ip in the below line to proceed
## Taking this as first argument
server_public_ip_address = $1
echo "The IP Address you entered is: ${server_public_ip_address}"

## Enter the path to your .pem file to access the server
## Taking this as second argument
path_to_pem_file = $2
echo "The path to .pem file you entered is: ${path_to_pem_file}"

## first login - Login as root
ssh -i $path_to_pem_file root@$server_public_ip_address

## create another user with the name you like
another_user_name = "ubuntu"
adduser $another_user_name

## giving user root privilages through sudo
## Now, when logged in as your regular user, 
## you can type sudo before commands to perform
## actions with superuser privileges.
usermod -aG sudo $another_user_name

## Setting Up a Basic Firewall
ufw allow OpenSSH
ufw enable

## exit from the server to login again using non root user
exit

## After this we can use the non root user 
## we created above to login by using below command
ssh -i $path_to_pem_file $another_user_name@$server_public_ip_address

echo "Done!"