I am searching for the best practice of securely deploying windows domain controller and exchange in a small-medium size network (50+ users, 20+ virtual servers). The topology is single firewall staying between wan and internal router (l3 switch) and firewall has a dmz leg. We have users, servers etc. vlans. How would you deploy them ?
Thanks.
The general rule is simple: Put the publicly-accessible servers in DMZ subnet and put the internally-used servers in the internal subnet. Configure your firewall accordingly.
Domain controller should be put in the internal subnet unless there is a need to make it publicly accessible??
Exchange server can be made publicly accessible or internal only depending on whether your email server is intended for private/public use.