Using zcs 5.0.5 Open Source mail server.

I am using a master server & having no backup like a slave server. So,in my case,suppose, any type of hardware failure of master server,will put me in trouble. Bcoz of a mail server,my company will become handicapped.

So,i want to know that how to create a slave mail server,that will have same data as the master server have.

Is it possible?

How?