Large Deployment advice. 10000 users

[Uchenna Nebedum]

Good Day all,

   If i wanted to use freeRADIUS to manage about 100 NAS each with about
1000 users, could i use a single server for all the NAS, if yes, what spec
of server.  And would MySQL still be the best database to use considering
performance or would Redis be better.  And what would be the best
configurations.

Please i need advice. Thanks a lot for any help.