Re: [Xen-users] xen 3.2 network problems

Sebastian Reitenbach
Thu, 31 Jan 2008 16:16:37 -0000

Sebastian Reitenbach <sebastia@l00-bugdead-prods.de> wrote:

> Hi,
>
> I try to get networking running with xen 3.2, but it seems I fail
miserably.
>
> I am on sles10sp1, with xen 3.2.0, and kernel rpm''s installed from
SP2.
>
> I configured in /etc/sysconfig/network the NETWORK_LIST:
>
>
NETWORK_LIST="bridge,0,default,00:DE:AD:BE:EF,192.168.8.13/24,dhcp-off"
>
> but an ifconfig xenbr0 still shows the mac address of peth0
> fe:ff:ff:ff:ff:ff.
>
> Initially, I had a bond interface on top of eth0 and eth1, the default
route
> was via the bond interface. after rebooting the xen kernel, it saw a
message
> that veth0 was missing, it said maybe because of not enough available
> loopback devices. I think more that this had to to with the bond0
interface.
> However, I followed the advice, and created some files
below /etc/modprobe.d
> with following contents:
>
> cat /etc/modprobe.d/*loop
> options loop max_loop=64
> options netloop nloopbacks=64
>
> Also, with the bond interface, when the ordinary network started, it
created
> the bond0 interface, and I was able to ping it for some seconds, until
xend
> was started, and it tried to add the bond0 to the xenbr0.
>
> when I now restart xend, I have veth0-veth63 and I have vif0.0-vif0.63. Is
> this the way it should be? I thought it would only create virtual
interfaces
> for the amount of physical interfaces on the dom0 available, at least this
> was how I have it seen on xen 3.0.4 and 3.1.0.
>
> Then I removed the bond0, and only had a eth0 interface, with IP
configured,
> the default route of the dom0 now via the eth0 interface. After a reboot,
> this was working well.
>
> So fine, then I added a vlan on top of the eth0, and rebooted. Without
> starting xend, I was able to communicate via eth0 and the vlan, then I
> started xen, and the tcpdump on the vlan interface stopped seeing packets
on
> that interface. The eth0 was still working. On xen 3.0.4 and xen3.1. I had
> no such problem with vlan interfaces, so is there anything I am missing?
>
The first thing was my fault, the default network-script changed from
network-bridge to network-multinet, but after changing this back, it did not
helped much.

Nevertheless, after some more hours fiddling around, it seems I got it
working as I want it to work. I had to take the network-bridge,
xen-network-common.sh, xen-script-common.sh, and the vif-bridge from a xen
3.0.4 version.

With the 3.2 network scripts, it throwed the vlan interfaces on top of my
bond0 interfaces away, but I need these later. With the 3.0.4 scripts, these
interfaces stay alive, and they work as expected after a xend start.
I had to define this in the xend-config.sxp file to be able to use the bond0
interface, instead of the eth0, as I wanted:
(network-script ''network-bridge netdev=bond0'')
The default route was set via the bond0 interface therefore I wonder why
xend start tried to fiddle with eth0 instead of bond0.

Can anybody explain me the reason why the vlan interfaces on top of bond0
are thrown away on xend start in the xen 3.2 version?


cheers