How to filter VPN clients with dynamic IPs?

Question

VPN

There is a Mikrotik, other Mikrotik clients connect to it via PPTP. It is necessary to make it so that it only allows connections from allowed addresses (in my case, from allowed ddns names). How to organize it?

Answer 1

You write a script, resolve names, put them in a sheet, a sheet in a firefol.

Answer 2

Write the necessary ddns names in the address-list, and create a rule in the input chain that prohibits tcp connections to port 1723, except for the corresponding address-list.