Channel Register

Red Hat meanders into hypervisor market

Chris Cox

Uh... virtualization history rewrite by Red Hat 

Posted Wednesday 18th June 2008 22:52 GMT

Just like they did with RHAS 2.1 (remember how Red Hat said that they didn't have an enterprise Linux release until RHAS 3?), now we have Red Hat abandoning Xen which they included in their last enterprise distribution. It was included to show the world Red Hat's commitment to virtualization and how, since they waited until Xen was stable, they were better situated to compete against Novell's SUSE.

Well... sounds like Red Hat didn't like what they were seeing from their own developers and decided to do ANOTHER history rewrite... sigh...

When Novell SLES 10 came out with Xen (prior to RHEL 5), Red Hat claimed it was junk and that NOBODY should use it.

See:

http://www.zdnet.com.au/news/software/soa/Xen-not-ready-for-prime-time-says-Red-Hat/0,130061733,139265136,00.htm

Then with RHEL 5, Red Hat declared Xen was truly enterprise ready and pushed their edition of Xen (yes... Red Hat went from Xen is junk to Xen is #1 in just a few months).

See:

http://www.redhat.com/rhel/server/advanced/virt.html (Xen)

And now? Bye, bye Xen... we meant KVM?? Oh really.... Red Hat needs to learn that switching horses all of the time causes grief for their customers. With that said, I think KVM is likely the Linux developed FOSS virtualization of choice for the future. But who knows what Red Hat will say next year...

Historical Aside: With regards to the elusive RHAS 2.1, I have a client I work for who pays for Red Hat support, every time they call in they would say... "upgrade to v3".... sheesh... Remember, Red Hat has publicly stated that RHAS 3 was their FIRST enterprise version (sigh). Sorry customer, you must have made a mistake.

... and on and on. Red Hat tends to say something new and different everytime you talk to them :)

Victor

also 

Posted Thursday 19th June 2008 10:32 GMT

why do they conveniently forget about Sun's xVM too?... it's also open source... and ubuntu also uses KVM... so being open source it's not an actual advantage when using red hat's solution...

nate

Xen is a PITA. KVM is a no-brainer. 

Posted Thursday 19th June 2008 10:32 GMT

Heart

"And now? Bye, bye Xen... we meant KVM?? Oh really.... Red Hat needs to learn that switching horses all of the time causes grief for their customers. With that said, I think KVM is likely the Linux developed FOSS virtualization of choice for the future. But who knows what Red Hat will say next year..."

It's worth getting rid of Xen.

And why? One word:

"Usability"

KVM is fantastic and is included in all relatively new kernels by default. It's hilarious because even though you may see a fight between Suse or Xen and Redhat.. Suse already supports KVM. So does Debian, so does everybody and their mom if they use a Linux kernel newer then 2.6.20 or so.

So it takes pretty much zero effort to get KVM implimented in Linux, because it's their by default. Redhat saying they are supporting KVM is about as difficult for them as announcing that they support the PCI bus.

KVM, basically, turns the linux kernel itself into a hypervisor. So instead of having to have a extra 'management console' with specialized commands for managing processes and starting and stopping VMs.. you can just use a X terminal. Want to 'pause' a VM? Hit ctrl-z! It's that simple. You can use top for monitoring VM performance. The VM runs just like any other application.

That's easy usability.

It uses Qemu for userland portion right now, but it can use pretty much anything. KVM kernel support is suppose to be fairly generic.

How many hypervisors you know support iSCSI? How about Fiberchannel or regular old drive image on NFS? It has logical volume support, sata support, pata support, scsi support. You can use pretty much any nic card ever invented. KVM gets proven support for all of that, because it inherents all the hardware support, networking, and storage management features of Linux by default. All of it proven and being widely used in all sorts of things.. _right_now_.

And not only having the same level of friendliness as Qemu or Virtualbox (minus the fancy gui) it supports all the 'killer' enterprise-ish features.

It has paravirtualized drivers for Windows and Linux. For high performance I/O. Without PV drivers, for example, it's basically nearly impossible to get better then 100Mb/s speeds out of a fully virtualized guest. With PV network drivers for Linux and Windows exceeding 1Gb/s performance is quite possible without any special hardware support.

It has the ability to do snapshots, to hotplug storage and memory. It has USB 1.1 support.

It can do live migrations from host to host with virtually no downtime.

Lots of performance tweaks and optimizations.

Basically there is no reason why it can't compete on a feature for feature and performance basis with fully-virtualized guests on Xen or Vmware ESX. (of course KVM, being relatively young needs to play some catch up. But this is no virtualbox were it's going to be desktop oriented, it can do that AND compete with hypervisors)

So on and so forth.

http://kvm.qumranet.com/kvmwiki/Status

So supporting KVM for Redhat is a no-brainer. It's better for Redhat, it's better for their customers. No need to install any extra software (beyond the modified qemu userland), no need to futz around with trying to shove a hypervisor underneath a perfectly working OS. No need to deal with Xen and it's PITA ways. It's there, it's always there, and it requires no extra effort by the end user besides firing up the VM and installing their favorite OS.

(well some networking hackery must be done, but it's pretty minor.)

This way virtualization becomes a integrated feature into the OS. It'll be common as a install of openoffice.org on a Linux machine and just as exciting.

Jim

And Sun's VirtualBox? 

Posted Thursday 19th June 2008 11:21 GMT

Sun's VirtualBox hasnt received a lot of air play, but it works well. Runs on Solaris, Linux, Windows, Mac OSX, and supports all the OSes that matter.

amanfromMars

@ Xen is a PITA. KVM is a no-brainer....... 

Posted Thursday 19th June 2008 13:00 GMT

....By nate Posted Thursday 19th June 2008 05:35 GMT

Right on the button, nate. ....... for Today. Tomorrow has AIMind of ITs Own.

Chris Cox

Missed point? 

Posted Friday 20th June 2008 04:11 GMT

My point is that with Red Hat you get an "enterprise" moving target, picking up technologies and dropping them (on top of the customer's head). You'll just have to trust me, customers don't like vendors that change their mind every 3 seconds. I mean, Red Hat went OUT OF THEIR way to sell the world on "superior" virtualization of their flagship enterprise RHEL 5... and some bought it hook, line and sinker.

As far as the merits of KVM, you and I are in agreement, I did mention that kvm is the future for virtualization... or is it?? I think we need to ask Red Hat that question a year from now... they'll probably want everyone to switch to something else... again...

tony trolle

@Xen is a PITA. KVM is a no-brainer 

Posted Saturday 21st June 2008 18:08 GMT

nice post nate.

usb 1.1 mmmmm need to find a good Gigabit ethernet NAS then.

I've had MS server 2008 iso's siting next to the cluster for over a month now still not had the time to play (hyper V.) One of the reasons is Virus removal jobs from MS machines :-(

Jack Pastor

Don'tcount out Xen so soon 

Posted Wednesday 25th June 2008 08:57 GMT

Yes, it is a PITA now, but Citrix is not letting their money go to waste. I suspect by 2009 Xen will be a very different beast with all the features of VMware and multiple times the performance. Quite likely, it will leave Hyper-V in the dust on all counts, but of course MSFT fans will choose that path just because ....

KVM is getting a lot of love from Linux geeks, and will certainly help fragment the market somewhat.

What we all need to consider is that everyone has nowhere to go but up EXCEPT VMware who has nothing to do but lose ......