[ubuntu-za] To virtualise or not to virtualise

[Charl Wentzel]

Hi Guys

My virtual server is on order and I will start setting it up early next
week.  For that part I don't see much problems.  My customer currently
have the following server which he wants to consolidate:

- Pastel Accounting server (Win Server 2003)
- GoldMine CRM (Win Server 2008 + MS SQL server)
- Linux Domain server with SAMBA (File and print server) & Web server
- Linux Firewall

Important: This is a small company with roughly 20 computer users, so
traffic volumes are low.

This is where experience counts:

a. Which of these servers can I safely virtualise on one server, e.g.
can the firewall be a virtual machine or should it always be a separate
physical machine?

b. Should the servers be virtualised as is, or should I split them up
further, e.g. Domain Server, SAMBA server and Web Server?

c. I would like to start with Ubuntu JeOS (just enough OS) and build the
Linux Servers up from there, rather that doing full Ubuntu Server on
each.  Is this a good idea or are there hidden security risks?

d. Since there is likely to be more than one Ubuntu server (and some
desktops in the future), I would like to set up apt-cache-ng.  Does it
matter which server this goes on to?... obviously not the Win 2008
Server :-)

e. They've show interest in an LTSP server.  My guess is that should be
a completely separate server?

I gut is that there must be some rule of thumb here, e.g. 
Number of Virtual servers <= number of CPU cores.  Are there such
guidelines?

Would love to hear from the guys who do this for a living.

Regards
Charl