How to send emails from a bash script using ssmtp?

Introduction

SSMTP is a tool that delivers emails from a computer or a server to a configured mail host.

SSMTP is not an email server itself and does not receive emails or manage a queue.

One of its primary uses is for forwarding automated email (like system alerts) off your machine and to an external email address.

Prerequisites

You would need the following things in order to be able to complete this tutorial successfully:

• Access to an Ubuntu 18.04 server as a non-root user with sudo privileges, and an active firewall installed on your server. To set these up, please refer to our Initial Server Setup Guide for Ubuntu 18.04

• An SMTP server along with SMTP username and password, this would also work with Gmail’s SMTP server, or you could setup your own SMTP server by following the steps from this tutorial on [https://www.digitalocean.com/community/tutorials/how-to-install-and-configure-postfix-as-a-send-only-smtp-server-on-ubuntu-16-04](How to Install and Configure Postfix as a Send-Only SMTP Server on Ubuntu 16.04)

Installing SSMTP

In order to install SSMTP you’ll need to first update your apt cache with:

sudo apt update

Then run the following command to install SSMTP:

sudo apt install ssmtp

Another thing that you would need to install is mailutils, to do that run the following command:

sudo apt install mailutils

Configuring SSMTP

Now that you have ssmtp installed, in order to configure it to use your SMTP server when sending emails you need to edit the SSMTP configuration file.

Using your favourite text editor opent the /etc/ssmtp/ssmtp.conf file:

sudo nano /etc/ssmtp/ssmtp.conf

You need to incldue the your SMTP configuration:

root=postmaster
mailhub=your_smtp_host.com:587
hostname=your_hostname
AuthUser=your_gmail_username@your_smtp_host.com
AuthPass=your_gmail_password
FromLineOverride=YES
UseSTARTTLS=YES

Save the file and exit.

Sending emails with SSMTP

Once your configuration is done, in order to send an email just run the following command:

echo "Here add your email body" | mail -s "Here specify your email subject" your_recepient_email@yourdomain.com

You can run this directly in your terminal or include it in your bash scripts.

Sending A File with SSMTP (optional)

If you need to send files as attachments, you can use mpack.

To install mpack run the following command:

sudo apt install mpack

Next, in order to send an email with a file attached, run the following command

mpack -s "Your Subject here" your_file.zip your_recepient_email@yourdomain.com

The above command would send an email to your_recepient_email@yourdomain.com with the your_file.zip attached.

Conclusion

SSMTP is a great and reliable way to implement SMTP email functionality directly in bash scripts.

For more information about SSMTP I would recommend checking the official documentation here.

Hope that this helps! Regards, Bobby