Update: It's sillier and sadder than I thought. See below.

Today (2007/11/12), Oracle announced Oracle VM, their free competitor to VMware and (Citrix) Xen. A few months ago, Oracle announced "Unbreakable Linux", which is their re-branding of Red Hat Enterprise Linux. There are already many free Red Hat flavors, including CentOS, but not too many companies have built business models on attempts to take Red Hat support business away from Red Hat.

Oracle has. They made many loud claims of being cheaper and better than RHEL, while claiming this wasn't an attack on Red Hat. Red Hat was pretty quiet about Oracle Linux, but did point out that Oracle's claims to be actively fixing bugs in RHEL (supposedly faster than Red Hat does) without forking RHEL were impossible -- as soon as there's a fix which isn't available from Red Hat, that's a fork.

There's been a lot of ill feeling both ways over this, but of course neither company is willing to publicly and unambiguously badmouth the other.

Today we see another step in Oracle's (Linux) plan: Oracle VM is free, but Oracle offers paid support. The best part is this, though:

What is the difference between Oracle VM and the virtualization that comes bundled with Oracle Enterprise Linux?

As part of the Unbreakable Linux Support program, Oracle supports virtualization that is included with Oracle Enterprise Linux 5. Please note that Oracle products are not supported to run in that environment. Any customer who wants to deploy Oracle products in a virtual environment should use Oracle VM, and subscribe to Oracle VM support. Oracle customers should refer to MetaLink note 466538.1

Translation: We sell RHEL5 (which includes Xen as part of the base price) but we don't like it, because we want you to pay more for Oracle VM instead. We cannot realistically either break or drop support for Xen, even though we'd really like to, but we do get to chose what "platforms" we support Oracle on, so we'll support Xen, and Oracle on Linux, but not Oracle on Xen. Please don't think too hard about that one. It makes our heads hurt!

Update 2007/11/13: I missed the fact that Oracle VM is based on Xen. This means Oracle wants to sell you "Unbreakable Linux", but wants to charge an extra $500 to virtualize its own software on "Oracle's" Linux platform. I thought they were claiming Oracle VM was better than RHEL's VM, but that can't stand even cursory scrutiny, given that they're basically the same code. Additionally, their

• Three times greater efficiency than current x86 based server virtualization products;

has to be in relation to VMware which is not paravirtualized, but there is no way Oracle's brand-new Xen build is significantly faster than Red Hat's Xen kernel, running on Red Hat's Linux distribution.

Given that Oracle now recommends RHEL + Xen (from Oracle) as a platform for running Oracle Database & Applications products, Oracle's lack of support for running on RHEL + Xen (when purchased from Red Hat) looks -- I was going to say even more absurd, but this can't be an oversight, so it's just transparent corporate greed.