Virtualisation has really been a game changer. One surprise of virtualisation
I have seen is that 10 physical servers can easily turning into over twenty virtual machines.
How is this possible I here you ask. Well the company in question had started with one server.
A exchange 2003 server and a domain controller. They had then upgraded the accounts system and bought a sql sever.
When the next upgrade had arrived and they had bulked at buying two more servers they just added another sql instance
and then spread the load over the back servers. So a IIS was installed on top of the file server. It worked and life went on and no new hardware had to be purchased. This had the effect that when the site had grown to ten servers over at least 5 years a major change was needed. This was a move to a datacentre and obvious result of that decision was virtualisation. Being a not for profite hyper V was at a very good price point so no saving was to be made by not having
This is as many companies have tried to save costs and not buy new physical servers
but just keep putting the applications spread over the existing servers.
One of the worst examples of virtual sprawl was the small office who had a max of 5 staff.
They had two physical servers running three virtual machines. Someone had obviously
sold them a complex solution. One physical server would have been ample.