Separation of servers to customers

[Faermark]

Faced with the problem:
I have several servers send.
I need to all messages that are sent a request for subscription (opt-in), regardless of Customers login, sent from one server.
How to do it?

Once noticed, if I add the sender's server to the client, I can not choose these options,
They apply only to systems.
It is not clear what it means to "List emails"

 

[twisted1919]

@Faermark - Only when you add servers from backend you can decide for what they are used for, so you should do it and assign servers to customers from there and lock them.
List emails means all emails that are sent in relation with lists, i.e: confirmation emails, welcome emails, unsubscribe emails, etc.