Installing vmware/xenserver on a linux operating system?

We're currently in the process of setting up a server here in a research environment. It would be ideal to use VMware ESXi, but (and I apologise if I get this completely wrong, I'm somewhat new to this) that needs to be installed on the machine initially instead of an OS correct? and then operating systems are installed as virtual machines? However the free version of it isn't suitable for us, the limitations on RAM would make the money we spent on the server redundant. We also looked at Cirtix XenServer free, which apparently has an upper RAM limit of 256GB, which again isn't enough (We have 512GB of RAM, over 4 CPUs which have 16 cores each). Now am I correct in assuming these virtualisation tools cannot be installed over an OS? Because it would be useful to install some linux based operating system on the server, which would have access to the full machine which we can log onto when running particularly intensive programs, but also have a number of virtual machines set up for other people to log into?

Is this possible?

Thanks in advance!

Solution 1:

A licensed copy of VMware ESXi, including vCenter (the Essentials Pack) is $500-$600US. There's no RAM limit, and it could accommodate up to three hosts.

Given the specifications of your physical hardware, the cost of obtaining the right VMware licensing is negligible.

Do the right thing!!