Re: [Xen-users] VM bridge doesn't pass traffic

[Ian Campbell <ian.campbell@xxxxxxxxxx>]

On Mon, 2016-01-18 at 10:06 +0100, David Winterstein wrote:
> Hey guys,
> 
> I've got a really strange issue with the networking on Debian 8.2 with
> Xen 4.4, probably particularly regarding the network bridge between the
> host machine and the vm.
> I recently set up a server cluster consisting of two Debian Jessie
> servers in a pretty basic configuration with Xen 4.4 from the official
> repositories. I then configured corosync, pacemaker and DRBD to sync a
> root partition between the two nodes and installed a Debian Jessie VM on
> the master node.
> Everything worked fine so far, but when I wanted to start configuring
> the vm two days ago, I found that though the eth0 interface was up and
> running a correctly configured IP the vm didn't have any access to the
> network.
> I then proceeded to check every possible thing I could think of and am
> now at my wit's end.
> The bridge is brought up by the default vif-bridge script and running,
> as brctl shows:
> 
> bridge nameÂÂÂÂÂbridge idÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂSTP enabledÂÂÂÂÂinterfaces
> xenbr0ÂÂÂÂÂÂÂÂÂÂ8000.0cc47a781e22ÂÂÂÂÂÂÂnoÂÂÂÂÂÂÂÂÂÂÂÂÂÂeth0
> ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂvif1.0
> 
> The required iptables rules are correctly generated:
> 
> Chain INPUT (policy ACCEPT 22281 packets, 3522K bytes)
> Âpkts bytes targetÂÂÂÂÂprot opt inÂÂÂÂÂoutÂÂÂÂÂsource
> destination
> 
> Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
> Âpkts bytes targetÂÂÂÂÂprot opt inÂÂÂÂÂoutÂÂÂÂÂsource
> destination
> ÂÂÂÂ0ÂÂÂÂÂ0 ACCEPTÂÂÂÂÂallÂÂ--ÂÂ*ÂÂÂÂÂÂ*ÂÂÂÂÂÂÂ0.0.0.0/0
> 0.0.0.0/0ÂÂÂÂÂÂÂÂÂÂÂÂPHYSDEV match --physdev-out vif1.0 --physdev-is-
> bridged
> ÂÂÂÂ0ÂÂÂÂÂ0 ACCEPTÂÂÂÂÂallÂÂ--ÂÂ*ÂÂÂÂÂÂ*ÂÂÂÂÂÂÂ0.0.0.0/0
> 0.0.0.0/0ÂÂÂÂÂÂÂÂÂÂÂÂPHYSDEV match --physdev-in vif1.0 --physdev-is-
> bridged
> 
> Chain OUTPUT (policy ACCEPT 18929 packets, 3285K bytes)
> Âpkts bytes targetÂÂÂÂÂprot opt inÂÂÂÂÂoutÂÂÂÂÂsource
> destination
> 
> Strangely, the vif interface is shown as DOWN in ip a on the dom0:
> 
> 5: vif1.0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq master
> xenbr0 state DOWN group default qlen 32
> ÂÂÂÂlink/ether fe:ff:ff:ff:ff:ff brd ff:ff:ff:ff:ff:ff

Does this indicate that the xenbr0 device itself is down, but vif1.0 is up?

Please can you post the full output of "ip addr show" in your dom0 and the
contents of your dom0 /etc/network/interfaces.

Ian.
_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxx
http://lists.xen.org/xen-users