Installed on a 64-bit CentOS 5.8 system.

## Configuring Apache for SNI

    # Configure CentOS Testing repo and install mod_gnutls
    wget http://dev.centos.org/centos/5/CentOS-Testing.repo -P /etc/yum.repos.d
    yum install mod_gnutls

Here's the package manifest:

    /etc/httpd/conf.d/mod_gnutls.conf
    /etc/httpd/conf/dhfile
    /etc/httpd/conf/rsafile
    /usr/lib64/httpd/modules/libmod_gnutls.so
    /usr/share/doc/mod_gnutls-0.2.0
    /usr/share/doc/mod_gnutls-0.2.0/LICENSE
    /usr/share/doc/mod_gnutls-0.2.0/NOTICE
    /usr/share/doc/mod_gnutls-0.2.0/README
    /var/cache/mod_gnutls_cache

Symlink the shared object file:

    ln -s /usr/lib64/httpd/modules/libmod_gnutls.so /etc/httpd/modules/mod_gnutls.so

Disable `ssl.conf` from loading

    mv /etc/httpd/conf.d/ssl.conf{,.old}

Edit `/etc/httpd/conf.d/mod_gnutls.conf` and uncomment (or add) the following:

    LoadModule gnutls_module modules/mod_gnutls.so
    AddType application/x-x509-ca-cert .crt
    AddType application/x-pkcs7-crl    .crl
    Listen 443

## Configuring Virtual Hosts

Let's say I want SNI for two virtual hosts:

-   `test.example.com`
-   test.eng.uiowa.edu (merely a CNAME for the above)

I create a configuration file for each in `/etc/httpd/conf.d/`. Let's start with `test.example.com`. Here's a skeleton:

    <VirtualHost 19.65.24.170:80>
        ServerName test.example.com
        DocumentRoot /var/www/html/test.example.com
        ServerAdmin support@test.example.com

        <Directory />
            Options FollowSymLinks -Indexes
            AllowOverride All
        </Directory>

        CustomLog /var/log/httpd/test.example.com-access.log combined
        ErrorLog /var/log/httpd/test.example.com-error.log
        LogLevel warn
    </VirtualHost>

    <VirtualHost 19.65.24.170:443>
        GnuTLSEnable on
        GnuTLSCertificateFile /etc/pki/tls/certs/test.example.com.crt
        GnuTLSKeyFile /etc/pki/tls/private/test.example.com.key

        ServerName test.example.com
        DocumentRoot /var/www/html/test.example.com
        ServerAdmin support@test.example.com

        <Directory />
            Options FollowSymLinks -Indexes
            AllowOverride All
        </Directory>

        CustomLog /var/log/httpd/test.example.com-access.log combined
        ErrorLog /var/log/httpd/test.example.com-error.log
        LogLevel warn
    </VirtualHost>

I do the same for the other virtual host and restart Apache. Done.