eap-tls certificates

I'm reading: http://deployingradius.com/documents/configuration/certificates.html It mentions, "You need to edit client.cnf only if you are using EAP-TLS. If not, then that file can be left as-is." Though it doesn't say, I'm assuming i need to edit the [req] and [client] sections? For the [client] section, do I need an entry for every unique client I plan on deploying a certificate to? I'm asking because I don't understand the emailAddress and commonName fields in this context. Finally, is there any documentation on how to scale this solution up to support 15k-20k users? I'm hoping something like LDAP or RDBMS is an option? -- Munroe Sollog (He/Him/His) Network Architect munroe@lehigh.edu