This article covers a version of Ubuntu that is no longer supported. If you are currently operate a server running Ubuntu 12.04, we highly recommend upgrading or migrating to a supported version of Ubuntu:
Reason: Ubuntu 12.04 reached end of life (EOL) on April 28, 2017 and no longer receives security patches or updates. This guide is no longer maintained.
This guide might still be useful as a reference, but may not work on other Ubuntu releases. If available, we strongly recommend using a guide written for the version of Ubuntu you are using. You can use the search functionality at the top of the page to find a more recent version.
You can host multiple SSL certificates on one IP Address using Server Name Indication (SNI).
Although hosting several sites on a single virtual private server is not a challenge with the use of virtual hosts, providing separate SSL certificates for each site traditionally required separate IP addresses. The process has recently been simplified through the use of Server Name Indication (SNI), which sends a site visitor the certificate that matches the requested server name.
SNI can only be used for serving multiple SSL sites from your web server and is not likely to work at all on other daemons, such as mail servers, etc. There are also a small percentage of older web browsers that may still give certificate errors. Wikipedia has an updated list of software that does and does not support this TLS extension.
SNI does need to have registered domain names in order to serve the certificates.
The steps in this tutorial require the user to have root privileges. You can see how to set that up in the Initial Server Setup Tutorial in steps 3 and 4.
Apache should already be installed and running on your VPS. If this is not the case, you can download it with this command:
sudo apt-get install apache2
For the purposes of this tutorial, both certificates will be self-signed. We will be working to create a server that hosts both example.com and example.org.
The SSL certificate has 2 parts main parts: the certificate itself and the public key. To make all of the relevant files easy to access, we should create a directory for each virtual host’s SSL certificate.
mkdir -p /etc/apache2/ssl/example.com
mkdir -p /etc/apache2/ssl/example.org
The next step is to enable SSL on the droplet.
sudo a2enmod ssl
Follow up by restarting Apache.
sudo service apache2 restart
When we request a new certificate, we can specify how long the certificate should remain valid by changing the 365 to the number of days we prefer. As it stands this certificate will expire after one year.
sudo openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /etc/apache2/ssl/example.com/apache.key –out /etc/apache2/ssl/example.com/apache.crt
With this command, we will be both creating the self-signed SSL certificate and the server key that protects it, and placing both of them into the new directory.
This command will prompt terminal to display a lists of fields that need to be filled in.
The most important line is "Common Name". Enter your official domain name here or, if you don't have one yet, your site's IP address.
You are about to be asked to enter information that will be incorporated into your certificate request. What you are about to enter is what is called a Distinguished Name or a DN. There are quite a few fields but you can leave some blank For some fields there will be a default value, If you enter '.', the field will be left blank. ----- Country Name (2 letter code) [AU]:US State or Province Name (full name) [Some-State]:New York Locality Name (eg, city) :NYC Organization Name (eg, company) [Internet Widgits Pty Ltd]:Awesome Inc Organizational Unit Name (eg, section) :Dept of Merriment Common Name (e.g. server FQDN or YOUR name) :example.com Email Address :firstname.lastname@example.org
Then go ahead and take the same steps for the second (example.org) domain:
sudo openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout /etc/apache2/ssl/example.org/apache.key -out /etc/apache2/ssl/example.org/apache.crt
Once you have the certificates saved and ready, you can add in your information in the virtual host files.
Although it’s not required, we can create two virtual host files to store virtual host information in separate files, copying the configuration from the default virtual host file.
sudo nano /etc/apache2/sites-available/example.com
sudo nano /etc/apache2/sites-available/example.org
Go ahead and open up each file and paste in the configuration below. This configuration is a simplified version of two separate configuration files: the default virtual server configuration file found at /etc/apache2/sites-available/default and the default SSL configuration located in /etc/apache2/sites-available/default-ssl.
Additionally, this configuration includes an important change that facilitates multiple SSL certificates. Whereas the default SSL configuration has the following line, specifying a certificate as the default one for the server,
the configuration below does not have a reference to a default certificate. This is key.
Overall, the default configuration files offer a variety of useful directives and additional configuration options that you can add to the virtual host. However, the following information will provide the server everything it needs to set up multiple SSL certificates on one IP address.
<VirtualHost *:80> ServerAdmin webmaster@localhost ServerName example.com DocumentRoot /var/www </VirtualHost> <IfModule mod_ssl.c> <VirtualHost *:443> ServerAdmin webmaster@localhost ServerName example.com DocumentRoot /var/www # SSL Engine Switch: # Enable/Disable SSL for this virtual host. SSLEngine on # A self-signed (snakeoil) certificate can be created by installing # the ssl-cert package. See # /usr/share/doc/apache2.2-common/README.Debian.gz for more info. # If both key and certificate are stored in the same file, only the # SSLCertificateFile directive is needed. SSLCertificateFile /etc/apache2/ssl/example.com/apache.crt SSLCertificateKeyFile /etc/apache2/ssl/example.com/apache.key </VirtualHost> </IfModule>
There are a few lines in these configuration files that need to be customized.
Set up both domains’ configurations. We still have more step before the separate SSL certificates will work on both servers.
The final step required to make sure that multiple certificates work on one VPS is to tell the server to listen on port 443. Add the bolded line to the apache ports configuration file.
sudo nano /etc/apache2/ports.conf
NameVirtualHost *:80 NameVirtualHost *:443 Listen 80 <IfModule mod_ssl.c> # If you add NameVirtualHost *:443 here, you will also have to change # the VirtualHost statement in /etc/apache2/sites-available/default-ssl # to
# Server Name Indication for SSL named virtual hosts is currently not # supported by MSIE on Windows XP. Listen 443 </IfModule> <IfModule mod_gnutls.c> Listen 443 </IfModule>
sudo a2ensite example.com sudo a2ensite example.org
(You can deactivate virtual hosts with the command:
sudo a2dissite example.com)
With all of the virtual hosts in enabled, restart apache.
sudo service apache2 restart
You should now be able to access both sites, each with its own domain name and SSL certificate.
You can view the sites both with and without the signed SSL certificates by typing in just the domain (eg. example.com or example.org) or the domain with the https prefix (https://example.com or https://example.org).
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