Thanks alot Michael.
I'll test and let you know if it works.


On Tue, Jul 1, 2014 at 3:04 PM, Michal Privoznik <mprivozn@redhat.com> wrote:
On 27.06.2014 13:33, abhishek jain wrote:
Hi

I need to run libvirt without ebtables support as it results in
following error while running VM....



sudo virsh start  instance-0000000b
error: Failed to start domain instance-0000000b
error: Error while building firewall: Some rules could not be created
for interface tapf733e054-fe: Failure to execute command '$EBT -t nat -A
libvirt-J-tapf733e054-fe  -j J-tapf733e054-fe-mac' : 'Unable to update
the kernel. Two possible causes:
1. Multiple ebtables programs were executing simultaneously. The ebtables
    userspace tool doesn't by default support multiple ebtables programs
running
    concurrently. The ebtables option --concurrent or a tool like flock
can be
    used to support concurrent scripts that update the ebtables kernel
tables.
2. The kernel doesn't support a certain ebtables extension, consider
    recompiling your kernel or insmod the extension.
.'.

I'd suggest reconfiguring kernel so it has CONFIG_BRIDGE_NF_EBTABLES, CONFIG_BRIDGE_EBT_T_FILTER and potentially others enabled.

Michal