John Center wrote:

I'm in the process of upgrading from v1.1.6 to v2.1.3, & I've been reviewing the 2.1.3 config files. I don't understand the purpose of the per_socket_clients config item in radiusd.conf. I think I understand how this is configured, but what is this used for? What benefits does this provide? Is it for security, server resources, etc?

The new "virtual server" functionality allows multiple old-style servers to be run from one process. In order for that to happen, each of the virtual servers need their own "listen" section, "authorize", etc. sections, and list of clients. However, it is often useful to share a list of clients between virtual servers. Rather than listing all of the clients each time, the list can be defined once, and referenced from multiple places. Alan DeKok.