Newbie User Manager questions

I did not realise that there was a seperate section on the User manager here, I have posted some questions in a different thread, but perhaps this is the best place for them;

"What spec of a machine should I really be running the User manger on at the core? I Intend on having the user manager authentication 10, 20 maybe even 30 rb450’s?

I have a limited amount of public ip’s which would be sitting on the wan side of the User Manager. I do not want to give out publics to everyone, but only to those who really need them, everyone else would be on a pool of privates set up on the User Manager.
Is it possible to specify a particular Public IP with a PPPOE USER/PASS using the User Manager and have it hand out the PUBLIC IP to the PPPOE SERVER at the other end of our network?

Is there anyway of backing up the users set up in the User manager?"

Hi,

I can only give you some ideas regarding the backup. Since the router os support scripting, you should be able to do backup.
First of all, you can export the user database with the export command.l or choose to backup the whole um with router settings etc.
This is done by this command: tool user-manager database save name=xxx

Once you have gotten so far and have the users backed up locally you should be able to sen the file via the FTP client that is implemented in the routerboard or make a FTP client connect to the rb and download the backup.