Thank you very much. It worked like a charm although I couldn't find that message in the libvirtd.log. Should I enable all three in /etc/sysctl.conf net.bridge.bridge-nf-call-ip6tables = 1 net.bridge.bridge-nf-call-iptables = 1 net.bridge.bridge-nf-call-arptables = 1 Thanks. Shi -- Shi Jin, PhD --- On Wed, 3/2/11, Stefan Berger <stefanb@xxxxxxxxxxxxxxxxxx> wrote: > From: Stefan Berger <stefanb@xxxxxxxxxxxxxxxxxx> > Subject: Re: Network Filter not working on RHEL-6 > To: "Shi Jin" <jinzishuai@xxxxxxxxx> > Cc: "libvirt Redhat" <libvir-list@xxxxxxxxxx>, jinzishuai@xxxxxxxxx > Date: Wednesday, March 2, 2011, 11:36 AM > On 03/01/2011 06:03 PM, Shi Jin > wrote: > > Hi there, > > > > I have been testing the Network Filter [1] feature of > libvirt with KVM on RHEL-5.6 and RHEL-6. On RHEL-5.6, it > works well except the $IP variable is not supported thus > cannot use the clean-filter. > > > > The major problem I found on RHEL-6 is that the > iptables rules introduced by nwfilter does not prevent any > traffic. The problem is that all traffic going to the VM > virtual NIC interface goes through the INPUT chain of the > iptables instead of the supposed-to-be FORWARD chain (this > is what the nwfilter rules are working on) so that none of > the rules have any effect. > > > > I am not sure whether this is a libvirt problem or > iptables problem. But it seems to me that changing from > RHEL-5.6 to RHEL-6, the network traffic works differently. > > > > Has anyone had similar experience? Any suggestion or > comments are welcome. > The libvirt log file probably would tell you something like > this here: > > To enable iptables filtering for the VM do 'echo 1 > > /proc/sys/net/bridge/bridge-nf-call-iptables'. > > Try that command and it should work. It became necessary > due to changed > default Linux kernel behaviour. > > Stefan > -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list