How can I put together services bettwen differents servers? [closed]

view story

http://serverfault.com – I have to run differents services in a lab enviroment where I'll have 6 computers working as servers, what services can I put together, and what cannot be, in order to prevent security risks, and considering that if one service goes down, affects less possible the function of the server farm, the services are: MySql Http for intranet Https DHCP IPP SMTP LDAP VPN SSH NTP DNS NFS I'll use linux (HowTos)