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/
Home Products Support Community News


Re: [Xen-users] xen network interfaces: How do I retrieve from an execut

To: "Fajar A. Nugraha" <fajar@xxxxxxxxx>
Subject: Re: [Xen-users] xen network interfaces: How do I retrieve from an executable running within domain0 the MAC of an frontend-(domainU)-network-interface ?
From: Kay Schubert <kayegypt@xxxxxx>
Date: Tue, 25 Aug 2009 09:10:34 +0200
Cc: xen-users@xxxxxxxxxxxxxxxxxxx
Delivery-date: Tue, 25 Aug 2009 00:11:31 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <7207d96f0908230737mba63baas3963f885f9a8605a@xxxxxxxxxxxxxx>
List-help: <mailto:xen-users-request@lists.xensource.com?subject=help>
List-id: Xen user discussion <xen-users.lists.xensource.com>
List-post: <mailto:xen-users@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=unsubscribe>
References: <200908231322.48688.kayegypt@xxxxxx> <7207d96f0908230737mba63baas3963f885f9a8605a@xxxxxxxxxxxxxx>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: KMail/1.9.10
Am Sunday 23 August 2009 16:37:25 schrieb Fajar A. Nugraha:
> On Sun, Aug 23, 2009 at 6:22 PM, Kay Schubert<kayegypt@xxxxxx> wrote:
> > Now each of those backend-interfaces gets assigned the
> > infamous FE:FF:FF:FF:FF:FF MAC. That turns out to be a problem if I try
> > to send packets from domain0 through the bridge-interface to any of the
> > domainU instances: the log tells me something along "ethernet source and
> > target are equal, can't send packets to myself".
> I had that problem on some dom0s as well :)
> Interestingly it doesn't occur when I split dom0 and domUs traffic on
> separate physical interfaces. For example :
> - eth0 for dom0's IP address
> - eth1 setup as trunk, created vlans and bridge on top of vlans, no IP
> address on those bridges, with domU using the bridges.
> > However, I had some success when I
> > manually assigned (by calling at domain0, for instance, "ip link set
> > vif13.1 address 00:16:3E:7D:D0:98") the MAC assigned to the
> > frontend-(domainU)-interface to the backend-(domain0)-interface as well.
> Actually, it doesn't matter what MAC you assign to the vif, as long as
> it's unique. At least that was the case on my setup. So I simply
> modify /etc/xen/scripts/vif-bridge, and generate a random MAC for
> every vif. It's not the same as domU's MAC.
Ah, you are conforming a suspicion I had ...

> > Now my question is: Supposed an executable is running within domain0, and
> > this executable has been handed the name of a Xen backend interface, is
> > there a way to obtain the MAC of the associated
> > frontend-(domainU)-interface ?
> If you still need domU's mac (for any reason), you could try this
> - xm network-list 13
> - xenstore-ls /local/domain/13/device/vif
Yes, five minutes after I had sent my question I looked up "xenstore" at 
Google, and came to http://wiki.xensource.com/xenwiki/XenStore, where a 
little script resides, that dumps the xenstore's content. And there it was. 
Its always the same: When you finally resolve to ask someone else, and think 
about how to shape your question, suddenly the answer is lurking somewhere 
near ...

> where "13" in that example is domU's ID. You could usually find out
> domU id from vif name (in your case vif13.1). I haven't tried running
> it from vif-bridge script though.
openSUSE doesn't use the scripts provided by Xen. They process xen network 
interfaces through scripts in /etc/sysconfig/network/scripts (as they do for 
all network interfaces, whatever kind) where one can add custom scripts. I 
will try my luck there.

Thank you very much!

Xen-users mailing list

<Prev in Thread] Current Thread [Next in Thread>