How To: Create CSR (Signed SSL Cert) for CentOS 5
To create a signed ssl certificate from a trusted certificate authority you will need to generate a csr, certificate signing request, which will then be sent to your CA where they can generate the ssl cert for you to install on the server. This is only necessary for production servers with a domain or sub domain pointing to it. For non-production use it is fine to just use a self signed cert that will not cost anything.
yum -y install mod_ssl openssl cd /etc/pki/tls/certs openssl genrsa -out new_ssl_cert.key 1024 openssl req -new -key new_ssl_cert.key -out new_ssl_cert.csr