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Work Underway To Return Xen Support To Fedora 13
Julie188 writes "Details on this are admittedly sketchy, but both Red Hat and Xen.org have gone on record promising that some kind of support for the Xen hypervisor is forthcoming for Fedora users. As we know, on Monday, Fedora 13 was released, chock full of features to appeal to business users. One of the ballyhooed improvements to 13 is virtualization — meaning KVM and only KVM — for Red Hat. Xen was dropped from Fedora a few releases ago and it hasn't come back in 13, except that 13 still supports Xen guests. Meanwhile, 'work is underway in Xen.org to add platform support to Fedora 13 post-release,' promises Xen.org's Ian Pratt."
As more new servers are deployed for virtualization, Xen superiority over KVM slowly, but surely disappears. First of all, all new tech has virtualization acceleration support in CPUs. Now, for example, using KVM in combination with paravirtualized network and storage drivers (which are packaged and used in Ubuntu as default), Ubuntu Server 10.04 LTS has the same speed and performance as guest as using Xen. Also huge improvements into libvirt stack and virt-manager have played role here - yes, I know, Xen also can use libvirt, but still - as it is more and more easier to deploy virtual machines, be it development or server environment. I have worked with Xen exclusively in the past for some three years, and most problems have been kernel patching issues and in fact, HVM support (because you still have to emulate some devices with quemu, which leaks like crazy, I guess that's reason why KVM now uses paravirtualized devices for net/storage). I don't have time to compile code for production servers, so if KVM is in kernel, and it is supported by kernel team and distribution, I will go for it. I was reserved And I guess lot of newcommers in virtualization will too.
In nutshell, Xen devs shoot in the foot here. Have they agreed to be included in main kernel three and be more welcome with patches, it would be more interesting competition here.
user@ubuntubox:~$ stfu This server is going down for shutdown NOW!
Protip: Look for the quotation marks, it's a quote, not added by the person publishing to the frontpage.
I don't post AC. I like my -1, Flamebaits. Trump/Sheen 2012 on the Batshit Insane ticket!
An exciting technology that I hoped to use, but just not up to the mark.
Protip: The word "protip" is not hyphenated.
There's no -1 for "I don't get it."
Fedora, not RHEL, is really where Xen belongs anyway. It's exactly the sort of mix of neat ideas, dirty hacks, and blatant wheel re-invention that could only have come from academia, and it was only ever made enterprise-grade by throwing heaps of money at it, and even then only for carefully tested configurations. Yes, it's pretty much single-handedly responsible for commoditizing virtualization, but the combination of the design and the lack of cooperation with the kernel community made it a nightmare to support. Xen is responsible for the existence of KVM because it showed such immense promise, and then delivered extreme frustration and pain.
Since Xen decided long ago it was going to be the center of its own universe, it's really in a great position to do cool experimental things that the kernel community would be more cautious about and the enterprise market wouldn't touch with a 10' pole without seeing a strong proof of concept first. That kind of innovation is a stated goal of the Fedora project.
The only technical advantage Xen enjoys right now is a lack of dependency on hardware virtualization features. Since it's impossible to buy a new machine that you can call a server with a straight face that lacks hardware virtualization, this is meaningless in the enterprise world, but Fedora (like other community distros) has a much broader scope, so there's still a real chance there for necessity to give birth to more invention, much like it did in the early days of Xen when x86 hardware virtualization was still a whisper in the halls at Intel and AMD.
Of course, Xensource/Citrix has already driven away most of the community that would have done this kind of pre-product development, so I'm not holding my breath, but it would be nice to see something more to come of all that work (and years of my own life) beyond simply supporting existing users.
There's no failure quite as dissatisfying as a complete and total solution to the wrong problem.
Plus, KVM has xenner that provides Xen compatible devices to virtual machines. I also saw some patches going into KVM that provide Hyper-V hypercalls to KVM. Right now they are fairly basic, but it is a start.
There is no doubt that KVM is the future. It is built into the kernel -- no dom0 patches required. RedHat is heavily investing in it. Note the sponsored oVirt project that integrates libvirt and FreeIPA to manage a network of virtual machine servers using kerberos and ldap as the security framework.
If you want XEN on Linux, then it is better to get Oracle Linux or OpenSUSE where XEN is included. It is really quite good and OpenSUSE has an excellent admin GUI for the whole system.
Seems to me they mostly get used to run multiple OS's that each run a single main app. Last time I looked modern OS's are quite capable of running multiple apps at the same time so unless you really need to run different OS's on the same machine (er why?) then what exactly is the point?
I've been using virtualization on non-x86 hardward for over 10 years. The ideas are not new to me.
I've used VMware, Xen, KVM, QEMU, VirtualBox, LMU, Jails, on Linux-based and BSD-based installs.
I started testing KVM in our lab about 6 months ago to be ready for the releases that have all come out recently. I've not been impressed. Performance sucks when compared to Xen and that is putting it nicely. Xen is lighter than VMware and VirtualBox. I don't really care about the controlling tools provided the CLI commands work. We have custom commands for Xen that can easily be migrated to KVM.
We're not going to use any virtualization that isn't part of the main production distributions, so Xen appears to be on the way out for us. I hope that KVM performance becomes similar and that the default setup matures to provide reasonable defaults with reasonable performance. Sadly, if I had to deploy new production VM infrastructure today, it would be ESX.
Someday KVM may catch Xen, but it hasn't yet, at least in the current packaged repository releases.
We recently purchased RHEL 5 Advanced Server after a few months of trying out Red Hat's virtualization options. One of the questions we had was whether Xen or KVM was the right tool to use going forward -- because we didn't want to adopt something then have it be replaced by new shiny almost immediately afterwards. We want to use a single virtualization platform for all our servers which means a migration from ESXi. I had already setup Xen and was starting to benchmark it.
We were emphatically told by several people at Red Hat (2 salespeople, our dedicated support engineer, and 2 other support staff) that Xen was the wrong direction and that only KVM would be supported in the future AND that existing support for Xen was being phased out. Yes I know Fedora isn't RHEL -- I've used Red Hat since 5.2 (way before Fedora Core). But this is just confusing and reminds me of the days when Red Hat Workstation was marketed.
Are there any competitive KVM solutions compared with Citrix's XenServer? The ease of management is great in Xenserver. Al tough ironically it's IMO harder to use Linux guests than windows guests since they only support a limited set of distros (and versions). If i want to run gentoo in a xenserver enviroment that's a lot of work with swapping kernels and grub config etc. That's just not feasible so i'm forced to run Cent OS, which I kinda dislike. Alternatives out there? How good are standard KVM tools?
Fedora 13 contains Xen hypervisor and tools, but it doesn't contain rpm package for a Xen dom0 capable kernel. There are unofficial Fedora rpm packages for a Xen dom0 capable kernel, based on the upstream pvops dom0 kernels (Linux 2.6.32). More information about Fedora Xen status and links to rpms see: http://fedoraproject.org/wiki/Features/XenPvopsDom0 . More information about available Xen dom0 kernel options see: http://wiki.xensource.com/xenwiki/XenDom0Kernels .
I saw a live virtual machine migration across processor families and types. Wish they would release that tech soon rather than work on getting Xen support back.
RHEL6 will support running as Xen guest, both PV and HVM. You can use RHEL5 as the Xen host (dom0), and run RHEL6 guests on it.
Does this version of glibc.x86_64 make my butt look big?
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
RHEL5 will fully support Xen until 2014 (which is when RHEL5 goes EOL). Redhat has stated this multiple times. Also upcoming RHEL6 runs as Xen guest, on RHEL5 Xen host/dom0. So there's no need to switch away from Xen.
Maybe this will force the Xen people to write maintainable code so we don't have to keep using 2.6.18 and backport everything.
+10. I used to be a REAL big fan of Xen. Did development work on it, and did some amazing stuff. Been to a number of the Xen conferences. Then I ran into Xen Cloud Platform. That converted me to KVM and I will never go back.
XCP is the most inane POS I have ever seen. The bad designs of Xen magnified by 10. In essence, the Xen developers have abstracted the System level interfaces, which has resulted in reinventing the wheel, needlessly and as badly as one can get. My general impression is that a bunch of Application programmers have decided to write an O.S. without the slightest clue as to what they are doing. Jeezus, Citrix, you need to put the Systems guys in charge first, and the Apps guys second. Apps guys are often dangerous in that they think they know System level work. Not doing this always leads to problems, and you are a prime example of what not to do. There's an old saying: Those who don't understand UNIX are doomed to reinvent it, badly. And that's exactly what you are doing.
The Xen guys shot themselves in the foot by essentially trying to fork Linux, by blowing off keeping up with mainstream. Now they are trying to repeat this again by creating a half-baked distro. C'mon guys, get a friggen clue. There's a reason why people do things the way they do it, and not the way you do it.
Stay away from Xen Cloud Platform. I'm looking forward to the KVM equivalent. At least there I know the Apps guys won't fancy themselves as OS people. And the OS guys will get things right, like they usually do.
Use the myoung dom0 repo. I've been running a Fedora 12 Dom0 for a few months now.
I so want to like KVM, but it's still fragile. I'll continue to help file and test KVM bugs so it's better than Xen at some point.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
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