FAQ Search Today's Posts Mark Forums Read
» Video Reviews

» Linux Archive

Linux-archive is a website aiming to archive linux email lists and to make them easily accessible for linux users/developers.


» Sponsor

» Partners

» Sponsor

Go Back   Linux Archive > CentOS > CentOS

 
 
LinkBack Thread Tools
 
Old 11-17-2010, 03:19 PM
Digimer
 
Default upgrading Centos-Xen when version 6 comes along

On 11/17/2010 11:02 AM, Rudi Ahlers wrote:
> Thanx Digimer,
>
> Just out of curiosity, are you part of the CentOS development team?
> Maybe the Wiki hasn't been updated with your info yet?
>
> Would you mind posting your findings to this list as well?

Nope, I'm independent. When I am done though, if people thinks it's good
enough quality, I'll make my docs available to the CentOS community
should they want to use them.

I think I'd rather post to the Xen and CentOS-virt lists, to about too
much duplication. If you want to follow along though, the very much in
progress links are:

- http://wiki.alteeve.com/index.php/Red_Hat_Cluster_Service_3_Tutorial
- http://wiki.alteeve.com/index.php/Xen_vs._KVM_Benchmark_-_Nov._2010

Neither are very useful at the moment though. I'm in the process of
migrating the documentation and my test setup to RHEL6. Things will be
stalled until that is done.

--
Digimer
E-Mail: digimer@alteeve.com
AN!Whitepapers: http://alteeve.com
Node Assassin: http://nodeassassin.org
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 11-17-2010, 03:38 PM
Paul Heinlein
 
Default upgrading Centos-Xen when version 6 comes along

On Wed, 17 Nov 2010, Rudi Ahlers wrote:

> Have anyone used both XEN & KVM before? What are your experiences
> with either, in comparison to each other? We've been using XEN for
> about 4 years now, and only use CentOS as our server platform. I'd
> hate to move to Debian or OpenSuse just for XEN, and I don't know
> KVM at all.

We run both Xen and KVM under CentOS 5 (on separate machines, of
course) and I haven't been able to spot significant performance
differences between the two.

RHEL 6 is supposed to contain a Xen-to-KVM migration tool, but I
haven't seen it in action.

It took me a while to figure out the KVM/libvirt XML configuration
files; some cookbook-style documentation for them would be a great
gift!

The biggest single up-front difference for me on CentOS machines was
that KVM hosts default to NAT on a private bridge while Xen hosts
default to straight bridging. Some network tweaks are necessary to get
KVM hosts to live on a straight bridge.

Also, if you assign MACs to your VMs at installation time (I do, for
DHCP- and DNS-related reasons), you should note that KVM MACs lives in
a different namespace: 54:52:00:xx:xx:xx.

I haven't done host migration with Xen, but it works quite well with
KVM -- once you have the shared storage and security mechanisms
configured properly.

--
Paul Heinlein <> heinlein@madboa.com <> http://www.madboa.com/
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 11-17-2010, 05:22 PM
Joe Pruett
 
Default upgrading Centos-Xen when version 6 comes along

On Wed, 17 Nov 2010, Rudi Ahlers wrote:
>> Have anyone used both XEN & KVM before? What are your experiences
>> with either, in comparison to each other? We've been using XEN for
>> about 4 years now, and only use CentOS as our server platform. I'd
>> hate to move to Debian or OpenSuse just for XEN, and I don't know
>> KVM at all.
one big issue that has kept me from switching from xen to kvm is that
the default init scripts for kvm don't have suspend/resume for guests
when the host os is rebooted. it doesn't even do a shutdown of the
guests, it just kills them. also, i haven't looked into whether you can
limit cpu/network usage easily with kvm as you can with xen. hopefully
some of these issues are fixed in the rhel6 kvm system.
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 11-17-2010, 05:29 PM
RedShift
 
Default upgrading Centos-Xen when version 6 comes along

On 11/17/10 19:22, Joe Pruett wrote:
> On Wed, 17 Nov 2010, Rudi Ahlers wrote:
>>> Have anyone used both XEN& KVM before? What are your experiences
>>> with either, in comparison to each other? We've been using XEN for
>>> about 4 years now, and only use CentOS as our server platform. I'd
>>> hate to move to Debian or OpenSuse just for XEN, and I don't know
>>> KVM at all.
> one big issue that has kept me from switching from xen to kvm is that
> the default init scripts for kvm don't have suspend/resume for guests
> when the host os is rebooted. it doesn't even do a shutdown of the
> guests, it just kills them. also, i haven't looked into whether you can
> limit cpu/network usage easily with kvm as you can with xen. hopefully
> some of these issues are fixed in the rhel6 kvm system.


Yeah that really ought to be fixed. I wonder why no-one at Red Hat thought of that...


Glenn
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 11-17-2010, 05:44 PM
 
Default upgrading Centos-Xen when version 6 comes along

> Nope, I'm independent. When I am done though, if people thinks it's
> good
> enough quality, I'll make my docs available to the CentOS community
> should they want to use them.
>
> --
> Digimer
> E-Mail: digimer@alteeve.com
> AN!Whitepapers: http://alteeve.com
> Node Assassin: http://nodeassassin.org

Thank you very very much Mr. D.

Really glad you are part of the CentOS community.

- aurf
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 11-17-2010, 08:13 PM
Pasi Kärkkäinen
 
Default upgrading Centos-Xen when version 6 comes along

On Tue, Nov 16, 2010 at 10:39:38AM +0000, Karanbir Singh wrote:
> On 11/16/2010 01:03 AM, Digimer wrote:
> > Once the bugs have been ironed out, I suspect that CentOS support will
> > follow soon after. There will be experimental kernels before then, but I
> > would not recommend them outside of test environments.
>
> If someone wants to put in the effort, and if there is sufficient demand
> for this to maintain as a part of centos-plus, hey - lets talk
>

I'm working on a RHEL6 Xen dom0 tutorial atm..

-- Pasi

_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 11-17-2010, 08:32 PM
Digimer
 
Default upgrading Centos-Xen when version 6 comes along

On 11/17/2010 04:13 PM, Pasi Kärkkäinen wrote:
> On Tue, Nov 16, 2010 at 10:39:38AM +0000, Karanbir Singh wrote:
>> On 11/16/2010 01:03 AM, Digimer wrote:
>>> Once the bugs have been ironed out, I suspect that CentOS support will
>>> follow soon after. There will be experimental kernels before then, but I
>>> would not recommend them outside of test environments.
>>
>> If someone wants to put in the effort, and if there is sufficient demand
>> for this to maintain as a part of centos-plus, hey - lets talk
>>
>
> I'm working on a RHEL6 Xen dom0 tutorial atm..
>
> -- Pasi

Posting off the ML.

Perhaps we could share notes? My focus in more on the clustering side of
things and I don't consider Xen-proper to be my strong suit. Maybe our
tutorials would compliment one another.

--
Digimer
E-Mail: digimer@alteeve.com
AN!Whitepapers: http://alteeve.com
Node Assassin: http://nodeassassin.org
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 11-17-2010, 08:41 PM
Digimer
 
Default upgrading Centos-Xen when version 6 comes along

On 11/17/2010 04:32 PM, Digimer wrote:
> On 11/17/2010 04:13 PM, Pasi Kärkkäinen wrote:
>> On Tue, Nov 16, 2010 at 10:39:38AM +0000, Karanbir Singh wrote:
>>> On 11/16/2010 01:03 AM, Digimer wrote:
>>>> Once the bugs have been ironed out, I suspect that CentOS support will
>>>> follow soon after. There will be experimental kernels before then, but I
>>>> would not recommend them outside of test environments.
>>>
>>> If someone wants to put in the effort, and if there is sufficient demand
>>> for this to maintain as a part of centos-plus, hey - lets talk
>>>
>>
>> I'm working on a RHEL6 Xen dom0 tutorial atm..
>>
>> -- Pasi
>
> Posting off the ML.

... or not. :P

--
Digimer
E-Mail: digimer@alteeve.com
AN!Whitepapers: http://alteeve.com
Node Assassin: http://nodeassassin.org
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 11-18-2010, 01:33 PM
Gabriel Tabares
 
Default upgrading Centos-Xen when version 6 comes along

> Also, if you assign MACs to your VMs at installation time (I do, for
> DHCP- and DNS-related reasons), you should note that KVM MACs lives in
> a different namespace: 54:52:00:xx:xx:xx.

You can change the allocated MAC address by editing the files in
/etc/libvirt/qemu .

Edit the <mac address='54:52:00:19:f2:ef'/> section and you're all set.

I am not sure if you need to restart libvirtd after making the changes,
as I have not got a machine I can test that at the moment.


_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 11-18-2010, 01:36 PM
Gabriel Tabares
 
Default upgrading Centos-Xen when version 6 comes along

> The biggest single up-front difference for me on CentOS machines was
> that KVM hosts default to NAT on a private bridge while Xen hosts
> default to straight bridging. Some network tweaks are necessary to get
> KVM hosts to live on a straight bridge.

Sorry, I forgot to add to this before.

If you want to use bridging in KVM you need to set up bridge interfaces
on the host (br0 and so on) and assign the main IP address to that
interface, instead of to the underlying physical one.

One more thing, if you assign a bridge to a VLAN interface, you do not
need to add the VLAN on the guest, just treat it as a normal interface
and the guest will take care of the tagging for you.

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

Thread Tools




All times are GMT. The time now is 12:48 PM.

VBulletin, Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2007, Crawlability, Inc.
Copyright ©2007 - 2008, www.linux-archive.org