Which Linux-Virtualization to choose for Server?

Hy, I got a brand new Intel i7 Server-System with 12GB Ram and I want to consolidate three other linux-servers onto this machine using virtualization. I want to use the harddisks (via a kind of LVM) in the server as storage as I got no SAN/IScsi. All Linux-VM's will run Debian-Linux, so no need for Windows-Support. I would prefer a bare-metal-virtualization (so where I dont have to maintain the os of "dom0"). The software should be free, even better open-source.

The virtual machines will run: PostgresSQL, a Lighttpd+PHP, a Tomcat-Server, a Mail-Server, a static-files Lighttpd.

The problem is, I cant decide which system to choose:

VMware EsXi: The Problem is the unsupported NIC in the server: It is a realtek-chip and as it is a hosted server I cant modifiy the hardware.

Citrix XenServer: I need the mangment Software to run under Linux, the Citrix-Software only runs on Windows. Bigger problem: You cant store the machines on the internal harddisk, you need a SAN.

XEN: Currently my favorite, but I found no managment software to use for showing the status of the virtual machines. I would have to setup a debian-system as dom0 and maintain it.

OpenVZ: I hate this, it never worked under debian right the way.

Main Problem is: the market is changing fast, so whatever I found on the internet was somehow outdated, so can anybody give me some advices? Thanks!

Solution 1:

Have you considered KVM?

Solution 2:

Maybe not the most popular answer, but if you love XEN, go with it. You probably know it best, are most familiar with using it, and you can use a mix of SNMP tools and monitoring agents to get a good idea of system status and performance. Why go with another solution if you have one you like and know you can work with?

My personal favorite inclination is ESXi which you said you can't use due to hardware. But that's because I'm most familiar with that solution :-)

Solution 3:

You will always have to update some OS or virtualization platform, called dom0 or something else, no matter what you choose. You do not seriously think ESX is without updates?

Given the choices and the OS in the VM's, I'd go for building a CentOS server as a Xen dom0 and then run the Debian domU's on it. CentOS will provide nice management tools, through GUI or console and is free in all the different meanings of the word.

As for the other options: ESX GUI management tools require Windows as well and Citrix is not what I would call a star on the Xen firmament. I don't know OpenVZ enough to say something useful about it.

As I always say at questions like this one: consider CentOS 5.4 and up with KVM, which is the future for Linux as a virtualization platform (and by that I mean that Xen probably is not, in the long run, as Red Hat will drop it from RHEL6).

Solution 4:

definitely KVM. Not only is it the true Linux hypervisor, but it's also the one most developed by Red Hat, who are known to be a major code contributor.

Since all you have is a single host, I wouldn't suggest you go with RHEV, but kvm is definitely the best choice in your case

Solution 5:

I would go with Xen. For monitoring you could use Nagios which has plugins for Xen monitoring, though this won't help you with VM management.
I run CentOS and there is Virtual Manager which is from RedHat.

I found what looks like a Debian port here