Linux Server Sends Email Alert when logged in as root

We can enable the linux server to automatically send a notification email to predefined email address everytime someone logs in as root to the host. To configure the automatic email alert notification to a default email address on each incident of root log on on the server, use the following guide.
Login to the server using as root ID.
Ensure that you’re at home directory of root. open the .bash_profile for editing using vi editor as shown below

vi .bash_profile

Scroll down to the end of the file and add the following line:

echo 'ALERT - Root Shell Access on:' `date` `who` mail -s "Alert: Root Access from `who cut -d"(" -f2 cut -d")" -f1`" user@example.com

Replace user@email.com with the actual email account address that you want to the root access alert notification been sent to. Note that you can change the text contains in the email alert too. The text starting with first ALERT is written as email body, and you can add in other info such as host name or change the wordings. The second Alert is the email title which you can enter your own text.