PPPoE is point-to-point interface, there’s no ‘networks’, only two addresses - and they can be anything you want. like local address is 192.168.255.0 and remote (user’s) address is 1.2.3.1
Then I don’t need to put an IP address of the same network that is my client equipment? Can I setup one invalid IP address (for internet, like, 192.168.1.1) on my pppoe server and give a valid IP address (valid for the internet) to my clients?
The local IP and remote IP don’t need to be in the same network?
I would suggest you create a loopback interface (see the wiki) with a valid IP, and use that as your local address. The local address should be a valid IP for the router, but no, it does not need to be in the same network.
Depending on what you’re doing with the router, the loopback IP can be used for a number of other things, and gives the router a reachable IP that is independent of any physical interface.
If you are going to be using OSPF or BGP then it will come in handy.
It also provides an IP address that belongs to the router, rather than one of its specific interfaces, and will always be “up” as long as the router is up; which lets you (or BGP, for instance) reach the router through any interface, as long as at least one physical interface is up and reachable.
You can use it as the local address for PPPoE or anything else that needs a router-side address. You can use it for radius, and SNMP, etc, irregardless of the state of your physical interfaces.
It can be used as the public IP for NAT.
Basically, its useful if the router is actually routing (using more than two interfaces). If the router is only using two interfaces (typically a public one towards the internet and a private one towards a customer), then you probably don’t need to bother with a loopback and can just use the IP on the public interface for any of those things.
I tried to configure the loopback interface. I did the follow:
I created a bridge with the name lobridge;
I cnofigurated the IP address on this interface;
I changed the PPPoE-server to run on this interface (lobridge);
But the clients don’t associate in pppoe-server in this configuration. If I put the pppoe server on the physical interface (ether1) everything works fine.
I did it, I put the IP on the loopback interface and everthing works fine! Thanks.
Now I’m with another small problem, I’ve latency when I use PPPoE authentication (with or without encryption).
The client radio is a Ubiquiti Nanostation M5 radio. If I use fixed IP I’ve 1ms or 2ms. If I active PPPoE authentication this time increase to 35ms or 40ms.