It would be nice if several routers could share the same IP Pool AND use an external radius server.
We use an external radius server for bw limits which is tied to our billing system. I'd like to have 4 pppoe servers drawing from one pool of ip's. Radius could hand out the ip's, but it has a hard time staying synchronized with which ip's are in use.
There would have to be some sort of synchronization to be sure that the master ip pool had a somewhat accurate idea of what ip's were in use on the slave boxes.
We need multiple pppoe servers for scalability and redundancy.
It would look like:
-slave pppoe server asks master to authenticate a user
-master asks radius for authentication and bw limits
-master grabs a ip from it's own master pool
-master tells slave user is valid, use this ip, and what the bw limit should be
-slave updates master when user leaves
-master querys all the slaves and removes any stale addresses at 10 min intervals