I am aware of the multitude of virtualization threads here but they all seem to be oldish and i'd like to have a brand new one ready for 2012.
I'm currently evaluating Xen, OpenVZ and KVM for virtualization purposes. I'm having trouble deciding what to use. The OS this will be running off of is Debian, preferably. The guest OS's will all be *nix based, mostly Debian as well. No windows, macos or other exotic stuff required. I have a single server, which has 16gigs of ram and a xeon processor on it. I also have a software raid 1 disk configuration with 3tb raid capacity.
I am setting up this environment so separate the sites my current server hosts by level of trust, and software version. For example, there are some sites i know might have security holes, others which should be perfectly secure, and others that require an archaic version of PHP.
All in all, i'd like to set up 3 different guests: one for trusted, one for untrusted, one for old php.
Part of my problem is managing backups properly: I enjoy using Bacula or duplicity to manage my backups because of incremental, encrypted backups. I do not want any of my client sites to ever have to go offline due to backup processes. I also only have 100 gigs of remote off-site backup space, so i want to use that wiseley, and not just dump all i have up there. Restoring from backups should be fast [no downloading huge iso files!].
I also want to do the disk space allocation right. I've read marvelous things about LVM and how it makes ones life easier. Assuming a raid 1 [two 3tb disks under raid1], how would you lay out your partition map?
I'd be happy if somebody could share his personal experiences, setup configurations and win/fails regarding different virtualization platforms, for a similar goal as mine.