Hello Kb,

theres myoungs repo available, he maintains a 2.6.32 kernel for fedora which has been ported to rhel/centos 6 as well.

http://xenbits.xen.org/people/mayoung/

perhaps this could be a base for cplus xen. for me it worked fine so far, but i whouldnt take it onto production until further testing.

i think i am not the only one who wants to stay with with xen :)

cheers,

juergen

Am 28.07.11 10:46, schrieb Karanbir Singh:

On 07/28/2011 08:01 AM, Juergen Gotteswinter wrote:

...

hi,

is there any chance to see a xen kernel + xen in centosplus probably? or is any recommend 3rd party repo available yet which provides this?

if someone was to step up and offer to manintain it, and a few people to help test it - CentOSPlus would welcome the rpms!

• KB

---

CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos

Hi,

A few more questions :)

On Thu, Jul 28, 2011 at 11:56 AM, John R. Dennison jrd@gerdesas.com wrote:

On Thu, Jul 28, 2011 at 10:53:23AM +0200, Juergen Gotteswinter wrote:

...

i think i am not the only one who wants to stay with with xen :)

Far from it.  Xen still has a place as a dom0.

What are the reasons for people staying with Xen as dom0, just the learning curve? Or are there some technical considerations as well?

Are there any good migration guides from xen to KVM?

Can xen domUs be used with KVM easily?

I am myself wondering should I learn KVM and go with C6 dom0 or to stick with C5 for now...

BR, Peter

On 07/28/2011 11:49 AM, Juergen Gotteswinter wrote:

Am 28.07.11 11:23, schrieb Peter Peltonen:

...

Hi,

A few more questions :)

On Thu, Jul 28, 2011 at 11:56 AM, John R. Dennisonjrd@gerdesas.com wrote:

...

On Thu, Jul 28, 2011 at 10:53:23AM +0200, Juergen Gotteswinter wrote:

...

i think i am not the only one who wants to stay with with xen :)

Far from it. Xen still has a place as a dom0.

What are the reasons for people staying with Xen as dom0, just the learning curve? Or are there some technical considerations as well?

Are there any good migration guides from xen to KVM?

Can xen domUs be used with KVM easily?

I am myself wondering should I learn KVM and go with C6 dom0 or to stick with C5 for now...

BR, Peter _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos

my experiences with KVM

• overcomittmend possible -> very bad in lots of producation systems

How is the *possibility* of overcomittment a bad thing. It gives you additional options. In many situation it *is* a good idea and KVM giving you the option should be a pro not a con. Nobody forces you to overcommit.

• vms run as qemu process which take often lots of more memory then

assigned to the vm, which could result in swapping (qemu overhead? dunno...)

Define "lots of more memory". Are you sure you are not looking at virtual memory and/or buffers?

• performance Issues, espacially io

Citations needed.

• cli tools arent as easy to use than xm / xl

If you use libvirt then you can keep using the same tools that you used for xen. The fact that the old tools seem to be easier to use i often a result of familiarity and not necessarily an indicator that the new tools are objectively worse.

I don't have any KVM guest in production yet but I've tested with both Linux and Windows 2008 guests and so far I hardly see any difference to my Xen guests.

Regards, Dennis

On Thu, Jul 28, 2011 at 11:23 AM, Peter Peltonen peter.peltonen@gmail.com wrote:

Hi,

A few more questions :)

On Thu, Jul 28, 2011 at 11:56 AM, John R. Dennison jrd@gerdesas.com wrote:

...

On Thu, Jul 28, 2011 at 10:53:23AM +0200, Juergen Gotteswinter wrote:

...

i think i am not the only one who wants to stay with with xen :)

Far from it.  Xen still has a place as a dom0.

What are the reasons for people staying with Xen as dom0, just the learning curve? Or are there some technical considerations as well?

KVM is not as mature as XEN. yet....? And if you want to use a so called Enterprise Operating System like CentOS, then you'd probably expect a stable and "enterprise" grade virtualization kernel as well.

KVM, IMO (and others as well ) is not enterprise ready yet.

On Thu, Jul 28, 2011 at 07:27:38AM -0400, Tom H wrote:

2. A so-called Enterprise Operating System like RHEL.

And your gratuitous edit of this point serves what purpose exactly?

John

On Thu, Jul 28, 2011 at 10:44:18AM -0400, Tom H wrote:

That blaming CentOS for the switch to KVM and the deprecation of Xen doesn't make sense since it's simply re-rpm'ing RHEL.

Ok, that makes sense and I fully agree :) I blame the lack of bacon for not understanding that earlier. Thanks for the clarification.

John

Le 28/07/2011 13:27, Tom H a écrit :

On Thu, Jul 28, 2011 at 6:31 AM, Rudi AhlersRudi@softdux.com wrote:

...

On Thu, Jul 28, 2011 at 11:23 AM, Peter Peltonen peter.peltonen@gmail.com wrote:

...

On Thu, Jul 28, 2011 at 11:56 AM, John R. Dennisonjrd@gerdesas.com wrote:

...

On Thu, Jul 28, 2011 at 10:53:23AM +0200, Juergen Gotteswinter wrote:

...

i think i am not the only one who wants to stay with with xen :)

Far from it. Xen still has a place as a dom0.

What are the reasons for people staying with Xen as dom0, just the learning curve? Or are there some technical considerations as well?

KVM is not as mature as XEN. yet....? And if you want to use a so called Enterprise Operating System like CentOS, then you'd probably expect a stable and "enterprise" grade virtualization kernel as well.

KVM, IMO (and others as well ) is not enterprise ready yet.

I'd edit what you've said in two ways.

1. The tools to manage KVM aren't as mature as the tools to manage Xen.

2. A so-called Enterprise Operating System like RHEL.

IMO, KVM in itself is not the problem, it is the lack of management solutions as mature as Vmware or XenServer, and lack of (other) Enterprise support, yet (for example ESXi is supported by Dell and others). Libvirt, in my opinion, and others, is not an Enterprise grade solution.

I am using KVM in a production environnement, for windows (2003 R2, 2008 R2), and Linux (Ubuntu, CentOS...). I don't see much difference with ESXi with the same kind of VMs (I never used Xen). But I am not using KVM with CentOS (or Red Hat), but under Debian, with Proxmox-ve. In the spirit of ESXi, it is a bare metal installer, which configure everything (bridge, LVM for snapshots, web interface management). I would not say it is as well known or mature as Vmware, but it fills my needs. The most interesting thing for me is the web management interface, which is very clear, permits to create or modify a VM, backup it, add a new storage, live migrate the VM (with shared storage), so it is a very convenient management solution, available from whatever system you want. Only a web browser supporting javascrip is needed, this is rather common these days...

And the most important point for me is that KVM is included in mainline kernel, that is available under every linux distribution (RHEL, Ubuntu, Debian, Suse, etc...), and will remain free source (GPL). So, if Proxmox-ve disappears, I can rather easily migrate to another solution. The other important point is that behind, it is standard Linux, not close as Vmware, so you can access eveything, add the package you want very easily.

One reason why RedHat discarded Xen was it was not included in the mainline kernel, so was difficult to maintain. You see, you have to compile your own kernel, that will not be supported upstream...

I am waiting to see the free (source) Java (so Linux) version of RHEVM, but I saw nothing appear yet, and I fear it will not be as handy Proxmox-ve Web interface and solution is, and not so open...

My two cents.

Alain