WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-users

Re: [Xen-users] Intermittent network in HVM domU

You checked the MAC and IP addresses, right?

--
Michael South

On May 6, 2011, at 12:38, Roberto Bifulco <roberto.bifulco2@xxxxxxxx> wrote:

Some more infos!
I run a simple ping test from my laptop to both domUs runinng on my server. The ping test shows that both domU suffers intermittent connectivity. More interestingly, when a domU network works, the other domU's network doesn't and viceversa.
So it seems a "network scheduler" problem. 

I'm starting searching about how can I customize the behavior of the IO scheduler for VNICs.
Roberto

2011/5/6 Roberto Bifulco <roberto.bifulco2@xxxxxxxx>
Todd,
thanks for your fast answer.
I'm going to install PVonHVM drivers for the linux domU to give them a try.
Today I realized that the intermittent connectivity is an issue only when a second domU is started, i.e, running just the linux domU works well.

Anyway, I should solve the issue even in the case of HVM domUs (without PV drivers), so still looking for any hint.
Thanks,
Roberto

2011/5/5 Todd Deshane <todd.deshane@xxxxxxx>
On Thu, May 5, 2011 at 8:17 AM, Roberto Bifulco
<roberto.bifulco2@xxxxxxxx> wrote:
> Dear Xen Community,
> I'm using Xen to virtualize some Windows and Linux servers.
> Currently I'm using two machines, one for production, which runs Xen 3.2.1
> with Debian5 Dom0 and the second one (Xen 4.0.1, openSuse 11.4 dom0) for
> development/testing.
> I'm experiencing some problems with an HVM linux domU over the development
> machine.
> In particular, the linux domU runs network services (web server, ssh), and,
> periodically, in an intermittent manner, the domU's network goes off.
> I realized that the vnc console attached to the domU still works, i.e., the
> domU is responsive, while the network doesn't work.
> The host machine is underloaded, i.e., it runs just two hvm domUs (the linux
> domU and an idle windows domU) and is configured in this way:
> one Intel processor with 4 cores,
> dom0 with 1 vcpu pinned to core 0
> other domains with 1 vcpu pinned to cores 1-3
> changing the dom0 credit scheduler configurations doesn't change this
> behaviour (e.g., assigning to dom0 a weight of 2048 while other domains have
> weight set to 256).
> Any suggestion on how I can solve this problem, or how can I figure out
> WHERE is the problem?

Have you tried installing the PVonHVM drivers in the Linux domU?

Have you tried disabling transmit checksum offloading?

Does a linux PV guest have the problem or just HVM?


Thanks,
Todd

> Thanks,
> Roberto
> --
> Roberto Bifulco, Ph.D. Student
> robertobifulco.it
> COMICS Lab - www.comics.unina.it
>
> _______________________________________________
> Xen-users mailing list
> Xen-users@xxxxxxxxxxxxxxxxxxx
> http://lists.xensource.com/xen-users
>



--
Todd Deshane
http://www.linkedin.com/in/deshantm
http://www.xen.org/products/cloudxen.html
http://runningxen.com/




--
Roberto Bifulco, Ph.D. Student
robertobifulco.it
COMICS Lab - www.comics.unina.it



--
Roberto Bifulco, Ph.D. Student
robertobifulco.it
COMICS Lab - www.comics.unina.it
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users