Basically, What I’m thinking to achieve is that possible that we can have 2 Mikrotik places within the same network, which can run their own PPPoE Server. I have the authority to switch clients on any of the PPPoE servers, which I can choose to move them into.
Is there any way? is there other that I can achieve to make this happen?
Not inside single L2 broadcast domain … PPPoE clients use broadcasts to discover PPOoE server and it’s a wild guess how they’ll react if they discover more than one. In best case they’ll use the first one to answer which won’t be exactly deterministic behaviour. If, however, you divide clients to two VLANs (on your access switches) and set up one PPPoE server per VLAN, you can deterministically affect which server serves each client.
You can have as many PPPoE servers as you want in the same L2 broadcast domain.
If you configure the client to request an offer for a particular service name, it will indicate this service name in its PADI, and only servers configured with that particular service name will respond. If you configure no service name at the client, its PADI will not indicate any service name and thus all servers will respond, regardless the service name configured at their side.
Even servers that use the same service name will back up each other and work the way @mkx has described - all of them respond to client’s PADI with a different delay, and the client chooses one of them so the load spreads across all available servers (typically, the delay of the response is proportional o the current load of the server).
It’s true that client can select PPOoE server according to service name. If tgat’s feasible depends if you as ISP have control over PPPoE clients or not. If you do have (because you mandate use of your CPEs which you fully control), then this is fine. If you don’t control PPOoE clients, then and you want deterministic behaviour, then you have to use other means of management. Use whatever fits your use case …
I’d say if the customer fiddles with the settings and empties the service name item, the PPPoE session should not come up due to username not found if the client chooses a wrong service. So not convenient support-wise but still manageable.