Resolution
Terms.Web server - web server is a server with standard Plesk product installed on where domains are hosted on.
Cmail - a standard Plesk server where Mail service is a primary service. Hosting service is not enabled for all the domains.
CDNS - a dedicated server where special software is installed on. This server has a dnscontroller role. Plesk Server Administrator cannot be installed on dnscontroller.
You can have the following types of network infrastructure with Expand product using:
1. One dedicated server with following products installed on.
* Expand product
* Centralized DNSOR
* Expand product
* Web serverOR
* Expand product
* Cmail server2. One dedicated server with following product installed on.
Web serverOR
Cmail serverOR
CDNSFinally you need to use at least three dedicate servers for following type of services:
CDNS, Cmail and Web server.
You need to use two dedicate servers for following type of services:
Cmail and Web server.
You need to use one dedicate server for following type of service:
Web server.