Enabling encryption on mosquitto

To enable encryption on mosquitto, you need first to have certificates. You can buy them from a company that is issuing certificates or you can generate them yourself as self-sign certificates.

Installing the openssl package

First, verify that you have the openssl package installed and it has a newer version (1.0.2g), as seen in the following screenshot:

If you don't have openssl installed you need to install it first, using the following command:

sudo apt install openssl on Ubuntu  

Or use the following command:

yum install openssl on CentOS/Redhat  

Generating your own certificates...