Installing SSL is quite different depending on OS target and targeted domains.

All OS distributions need to have OpenSSL installed and mod_ssl enabled in Apache.

Please carefully read through all the documentation for your OS distribution BEFORE attempting to enable SSL on your server.

To create a self-signed SSL certificate in Ubuntu 12.04 LTS & 14.04 LTS

Login to a terminal as the root user

sudo -i

Install OpenSSL

apt-get install openssl

Create a directory for your certificates

mkdir /etc/apache2/ssl/

Create the certificates

openssl req -x509 -nodes -days 365 -newkey rsa:2048 -out /etc/apache2/ssl/Sentora.crt -keyout /etc/apache2/ssl/Sentora.key

Fill in all the information that is needed when prompted.

Then follow the installation instructions.

(do not forget to come back to user level with exit)

To create a self-signed SSL certificate in CentOS 6.X

login to a terminal as the root user

Install OpenSSL

yum install mod_ssl openssl

Create the certificates

openssl req -x509 -nodes -days 365 -newkey rsa:2048 -out /etc/pki/tls/certs/Sentora.crt -keyout /etc/pki/tls/certs/Sentora.key

Fill in all the information that is needed when prompted.

Then follow the installation instructions.

 

Prepare a purchased SSL certificate for server installation.

Download your files from your place of purchase to your computer.

You should receive 3 files ..........

AddTrustExternalCARoot.crt

PositiveSSLCA2.crt

&

domain_com.crt

Open a text editor of your choice and copy the code from AddTrustExternalCARoot.crt followed by the code from PositiveSSLCA2.crt in that order.

Save the file and name it domain_com.ca-bundle.crt

You will also need to download the domain_com.csr file from your place of purchase.

Then follow the installation instructions.

 

To purchase granted SSL Certificates

GoDaddy

Go Get SSL

StartCom

Or try Google.

 

To obtain a free certificate

Let's Encrypt

Start SSL