How to Set SSH Login Email Alerts in Linux Server

How to Set SSH Login Email Alerts in Linux Server

To carry out this tutorial, you must have root level access on the server and a little knowledge of nanoor vi editor and also mailx (Mail Client) installed on the server to send the emails. depending upon your distribution you can install mailx client using one of the following commands.

On Debian/Ubuntu/Linux Mint

# apt-get install mailx

On RHEL/CentOS/Fedora

# yum install mailx

Set SSH Root Login Email Alerts

Now login as root user and go to root’s home directory by typing cd /root command.

# cd /root

Next, add an entry to the .bashrc file. This file sets local environment variables to the users and does some login tasks. For example, here we setting a an email login alert.

Open .bashrc file with vi or nano editor. Please remember .bashrc is a hidden file, you won’t see it by doing ls -l command. You’ve to use -a flag to see hidden files in Linux.

# vi .bashrc

Add the following whole line at the bottom of the file. Make sure to replace “ServerName” with ahostname of your Server and change “your@yourdomain.com” with a your email address.

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

Save and close the file and logout and log back in. Once you login via SSH, a .bashrc file by default executed and sends you an email address of the root login alert.

Sample Email Alert

ALERT - Root Shell Access (Database Replica) on: Thu Nov 28 16:59:40 IST 2013 tecmint pts/0 2013-11-28 16:59 (172.16.25.125)

Set SSH Normal User Login Email Alerts

Login as normal user (tecmint) and go to user’s home directory by typing cd /home/tecmint/command.

# cd /home/tecmint

Next, open .bashrc file and add the following line at end of the file. Make sure to replace values as shown above.

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

Save and close the file and logout and login again. Once you login back again, a .bashrc file executed and sends you an email address of the user login alert.

This way you can set an email alert on any user to receive login alerts. Just open the user’s .bashrcfile which should located under the user’s home directory (i.e. /home/username/.bashrc) and set the login alerts as described above.