Setting a new expiration date on a .pem file for apache
I've created a self-signed .pem file for encryption by running make <hostname>.pem in /etc/pki/tls/certs for use in my httpd.conf file.
The expiration date for the certificate is coming up and I usually just create a new .pem file to get around this but that requires that people that browse to the site install the new certificate. I'm relatively sure that's not the "correct" way to handle this situation.
What is the proper procedure for extending/resetting the expiration date on the existing .pem file?