Issue while Launching Instances

Hi,

While i try to Launch a instance am getting the status of the instance as " failed to spawn"

The log detail of "/var/log/nova/nova-compute.log"
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2011-07-08 06:31:32,054 AUDIT nova.compute.manager [XWWDD65SIXJ9UGDSZF5S admin CNext] instance 12: starting...
2011-07-08 06:31:32,149 DEBUG nova.rpc [-] Making asynchronous call on network ... from (pid=2264) multicall /usr/lib/pymodules/python2.6/nova/rpc.py:481
2011-07-08 06:31:32,149 DEBUG nova.rpc [-] MSG_ID is aba76a9ad02745319150d6ecf819d33c from (pid=2264) multicall /usr/lib/pymodules/python2.6/nova/rpc.py:484
2011-07-08 06:31:32,510 DEBUG nova.compute.manager [-] instance network_info: |[[{u'injected': True, u'bridge': u'br100', u'cidr_v6': None, u'cidr': u'0.0.0.4/29', u'id': 1}, {u'label': u'10.0.0.0/24_0', u'broadcast': u'0.0.0.7', u'ips': [{u'ip': u'0.0.0.6', u'netmask': u'255.255.255.248', u'enabled': u'1'}], u'mac': u'02:16:3e:66:63:10', u'rxtx_cap': 0, u'dns': [u'8.8.4.4'], u'gateway': u'0.0.0.1'}]]| from (pid=2264) _run_instance /usr/lib/pymodules/python2.6/nova/compute/manager.py:295
2011-07-08 06:31:32,516 DEBUG nova.utils [-] Attempting to grab semaphore "ensure_bridge" for method "ensure_bridge"... from (pid=2264) inner /usr/lib/pymodules/python2.6/nova/utils.py:600
2011-07-08 06:31:32,516 DEBUG nova.utils [-] Attempting to grab file lock "ensure_bridge" for method "ensure_bridge"... from (pid=2264) inner /usr/lib/pymodules/python2.6/nova/utils.py:605
2011-07-08 06:31:32,516 DEBUG nova.utils [-] Running cmd (subprocess): ip link show dev br100 from (pid=2264) execute /usr/lib/pymodules/python2.6/nova/utils.py:143
2011-07-08 06:31:32,674 DEBUG nova.virt.libvirt_conn [-] instance instance-0000000c: starting toXML method from (pid=2264) to_xml /usr/lib/pymodules/python2.6/nova/virt/libvirt/connection.py:1035
2011-07-08 06:31:32,681 DEBUG nova.virt.libvirt_conn [-] instance instance-0000000c: finished toXML method from (pid=2264) to_xml /usr/lib/pymodules/python2.6/nova/virt/libvirt/connection.py:1039
2011-07-08 06:31:32,682 INFO nova [-] called setup_basic_filtering in nwfilter
2011-07-08 06:31:32,682 INFO nova [-] ensuring static filters
2011-07-08 06:31:32,695 DEBUG nova.virt.libvirt.firewall [-] Adding security group rule: <nova.db.sqlalchemy.models.SecurityGroupIngressRule object at 0x4504890> from (pid=2264) instance_rules /usr/lib/pymodules/python2.6/nova/virt/libvirt/firewall.py:663
2011-07-08 06:31:32,695 DEBUG nova.virt.libvirt.firewall [-] Adding security group rule: <nova.db.sqlalchemy.models.SecurityGroupIngressRule object at 0x4504e50> from (pid=2264) instance_rules /usr/lib/pymodules/python2.6/nova/virt/libvirt/firewall.py:663
2011-07-08 06:31:32,695 DEBUG nova.utils [-] Attempting to grab semaphore "iptables" for method "apply"... from (pid=2264) inner /usr/lib/pymodules/python2.6/nova/utils.py:600
2011-07-08 06:31:32,695 DEBUG nova.utils [-] Attempting to grab file lock "iptables" for method "apply"... from (pid=2264) inner /usr/lib/pymodules/python2.6/nova/utils.py:605
2011-07-08 06:31:32,696 DEBUG nova.utils [-] Running cmd (subprocess): sudo iptables-save -t filter from (pid=2264) execute /usr/lib/pymodules/python2.6/nova/utils.py:143
2011-07-08 06:31:32,707 DEBUG nova.utils [-] Running cmd (subprocess): sudo iptables-restore from (pid=2264) execute /usr/lib/pymodules/python2.6/nova/utils.py:143
2011-07-08 06:31:32,719 DEBUG nova.utils [-] Running cmd (subprocess): sudo iptables-save -t nat from (pid=2264) execute /usr/lib/pymodules/python2.6/nova/utils.py:143
2011-07-08 06:31:32,731 DEBUG nova.utils [-] Running cmd (subprocess): sudo iptables-restore from (pid=2264) execute /usr/lib/pymodules/python2.6/nova/utils.py:143
2011-07-08 06:31:32,743 DEBUG nova.utils [-] Running cmd (subprocess): mkdir -p /var/lib/nova/instances/instance-0000000c/ from (pid=2264) execute /usr/lib/pymodules/python2.6/nova/utils.py:143
2011-07-08 06:31:32,750 INFO nova.virt.libvirt_conn [-] instance instance-0000000c: Creating image
2011-07-08 06:31:32,766 DEBUG nova.utils [-] Attempting to grab semaphore "00000004" for method "call_if_not_exists"... from (pid=2264) inner /usr/lib/pymodules/python2.6/nova/utils.py:600
2011-07-08 06:31:32,766 DEBUG nova.utils [-] Running cmd (subprocess): cp /var/lib/nova/instances/_base/00000004 /var/lib/nova/instances/instance-0000000c/kernel from (pid=2264) execute /usr/lib/pymodules/python2.6/nova/utils.py:143
2011-07-08 06:31:32,793 DEBUG nova.utils [-] Attempting to grab semaphore "ac3478d69a3c81fa62e60f5c3696165a4e5e6ac4" for method "call_if_not_exists"... from (pid=2264) inner /usr/lib/pymodules/python2.6/nova/utils.py:600
2011-07-08 06:31:32,794 DEBUG nova.utils [-] Running cmd (subprocess): qemu-img create -f qcow2 -o cluster_size=2M,backing_file=/var/lib/nova/instances/_base/ac3478d69a3c81fa62e60f5c3696165a4e5e6ac4 /var/lib/nova/instances/instance-0000000c/disk from (pid=2264) execute /usr/lib/pymodules/python2.6/nova/utils.py:143
2011-07-08 06:31:32,904 DEBUG nova.utils [-] Attempting to grab semaphore "local_20" for method "call_if_not_exists"... from (pid=2264) inner /usr/lib/pymodules/python2.6/nova/utils.py:600
2011-07-08 06:31:32,904 DEBUG nova.utils [-] Running cmd (subprocess): qemu-img create -f qcow2 -o cluster_size=2M,backing_file=/var/lib/nova/instances/_base/local_20 /var/lib/nova/instances/instance-0000000c/disk.local from (pid=2264) execute /usr/lib/pymodules/python2.6/nova/utils.py:143
2011-07-08 06:31:32,969 ERROR nova.exception [-] Uncaught exception
(nova.exception): TRACE: Traceback (most recent call last):
(nova.exception): TRACE: File "/usr/lib/pymodules/python2.6/nova/exception.py", line 87, in _wrap
(nova.exception): TRACE: return f(*args, **kw)
(nova.exception): TRACE: File "/usr/lib/pymodules/python2.6/nova/virt/libvirt/connection.py", line 590, in spawn
(nova.exception): TRACE: block_device_mapping=block_device_mapping)
(nova.exception): TRACE: File "/usr/lib/pymodules/python2.6/nova/virt/libvirt/connection.py", line 894, in _create_image
(nova.exception): TRACE: 'gateway6': mapping['gateway6'],
(nova.exception): TRACE: KeyError: 'gateway6'
(nova.exception): TRACE:
2011-07-08 06:31:32,970 ERROR nova.compute.manager [-] Instance '12' failed to spawn. Is virtualization enabled in the BIOS? Details: 'gateway6'
(nova.compute.manager): TRACE: Traceback (most recent call last):
(nova.compute.manager): TRACE: File "/usr/lib/pymodules/python2.6/nova/compute/manager.py", line 311, in _run_instance
(nova.compute.manager): TRACE: self.driver.spawn(instance, network_info, bd_mapping)
(nova.compute.manager): TRACE: File "/usr/lib/pymodules/python2.6/nova/exception.py", line 93, in _wrap
(nova.compute.manager): TRACE: raise Error(str(e))
(nova.compute.manager): TRACE: Error: 'gateway6'
(nova.compute.manager): TRACE:

pls help