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Open Source and the "Xen" of Xen
willdavid writes "In a follow-up to his original look at what happened to Xen, Jeff Gould talks to XenSource CTO Simon Crosby. Usually we hear about how open source provides freedoms for end users. However, this article talks about the difficulty a small software developer has with an open source license, in particular, the need to prevent Red Hat, IBM or Novell from running away with all the business revenue."
I haven't read the FA yet, but this isn't the first time this concern has been raised. The OGP, from the beginning, have been struggling with the issue of some other hardware vendor legally taking OGP graphics chip designs and making their own version, thereby crusing the OGP out of existence.
Funny this should come up today - I just spent the weekend playing with Xen, trying to combine a couple of my household servers to get better utilization and to save power.
I've been playing around with VMWare since it initially came out, including a production install of v4.5 at work to virtualize NT4 machines so that our LAN goons won't complain, and I've always found it extraordinarily easy to use. From a "get it running" perspective, the damn thing's idiot-proof. Fire it up, boot off some install media (even if it's Knoppix, and you're going to image the system from elsewhere), and you're golden.
Xen? Eh, not so easy if you're not starting with a clean install of a Xen-aware OS. Lots of hours screwing with configurations, swapping kernels, messing with pygrub, and scratching my head as to why it wasn't doing anything, or was crashing with some cryptic error. Some of this is a result of the paravirtualization approach, as it requires some guest changes, but nobody's really published a good, generalized guide to native->domU migration. (Yes, I know about the CentOS one, and while it was some help, it was also wrong at some points, as it's never been updated for a CentOS 4.5 domU.)
My take is this - the (non-Xen) tools bundled with RHEL5 (well, CentOS 5, really) are, um, overly simplistic at best and completely unhelpful at worst. Graphical tools be damned - by the end it was me, the text editor, and xm on the command line.
I did get it up and running, and when given its own disks, the performance is impressive. It (unscientifically) *feels* faster than a Linux VM on Linux-hosted VMWare (desktop version). Now my web/mail server and house/firewall server have been combined. Tonight, I'll collapse in one more server. I'm quite confident I can do it in a reasonable amount of time, now that I've figured out most of the gotchas. Plus, sounds like a good thing to document and post so that others might not have to fight through quite as much as I did.
In an enterprise environment, the management tools make or break you. When I'm managing a handful of machines, doing it myself is annoying but acceptable. When I'm virtualizing a datacenter and need tools to convert machines, manage their resources, manage their operations, etc., then management toys become the make-or-break part of the deal. We all assume your virtualizer works - now let's see what makes our lives easier managing this strange new world.