The examples below send an email when someone logs into your server. For this to work, your server must be able to send mail using the mail command.

CentOS

Open the file ~/.bash_profile in a text editor.

Append the following lines:

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IP="$(echo $SSH_CONNECTION | cut -d " " -f 1)"
HOSTNAME=$(hostname)
NOW=$(date +"%e %b %Y, %a %r")

echo 'Someone from '$IP' logged into '$HOSTNAME' on '$NOW'.' | mail -s 'SSH Login Notification' YOUR_EMAIL_ADDRESS

 

Ubuntu/Debian

 

Open the file ~/.bashrc in a text editor.

 

Append the following lines:

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IP="$(echo $SSH_CONNECTION | cut -d " " -f 1)"
HOSTNAME=$(hostname)
NOW=$(date +"%e %b %Y, %a %r")

echo 'Someone from '$IP' logged into '$HOSTNAME' on '$NOW'.' | mail -s 'SSH Login Notification' YOUR_EMAIL_ADDRESS