Hi all, I was running an openstack on Centos 6.5 (controller + network + 4 compute nodes) and all was working fine utnil upgrade to Centos 6.6. When I try to spawn new instance I get an error on dashboard:

Error: No valid host was found. Exceeded max scheduling attempts 3 for instance

and scheduler.log from controller:

2015-03-03 16:33:37.416 1719 ERROR nova.scheduler.filter_scheduler [req-381413bc-59ab-4837-93fc-6a5e35fc6a84 66a609d76a5d487196f043b06874f910 8bc83a160b424cbaa6c95308b333669f] [instance: 9ce61f67-b3c3-4e81-ae73-9718d408400f] Error from last host: compute0 (node compute0): [u'Traceback (most recent call last):\n', u'  File "/usr/lib/python2.6/site-packages/nova/compute/manager.py", line 1328, in _build_instance\n    set_access_ip=set_access_ip)\n', u'  File "/usr/lib/python2.6/site-packages/nova/compute/manager.py", line 393, in decorated_function\n    return function(self, context, *args, **kwargs)\n', u'  File "/usr/lib/python2.6/site-packages/nova/compute/manager.py", line 1740, in _spawn\n    LOG.exception(_(\'Instance failed to spawn\'), instance=instance)\n', u'  File "/usr/lib/python2.6/site-packages/nova/openstack/common/excutils.py", line 68, in __exit__\n    six.reraise(self.type_, self.value, self.tb)\n', u'  File "/usr/lib/python2.6/site-packages/nova/compute/manager.py", line 1737, in _spawn\n    block_device_info)\n', u'  File "/usr/lib/python2.6/site-packages/nova/virt/libvirt/driver.py", line 2291, in spawn\n    write_to_disk=True)\n', u'  File "/usr/lib/python2.6/site-packages/nova/virt/libvirt/driver.py", line 3480, in to_xml\n    disk_info, rescue, block_device_info)\n', u'  File "/usr/lib/python2.6/site-packages/nova/virt/libvirt/driver.py", line 3294, in get_guest_config\n    flavor)\n', u'  File "/usr/lib/python2.6/site-packages/nova/virt/libvirt/vif.py", line 384, in get_config\n    _("Unexpected vif_type=%s") % vif_type)\n', u'NovaException: Unexpected vif_type=binding_failed\n']

On the compute0 I dont see any specific errors:

2015-03-03 17:20:48.143 2481 INFO neutron.agent.securitygroups_rpc [req-efcb1c0d-1d2f-4095-b944-3c0246cb97e4 None] Security group member updated [u'ce582782-b451-4aef-b4c6-fde44c33e185']
2015-03-03 17:20:52.803 2481 INFO neutron.agent.securitygroups_rpc [req-b8d0b8de-5ac6-49c3-9217-e9881fda83c7 None] Security group member updated [u'ce582782-b451-4aef-b4c6-fde44c33e185']
2015-03-03 17:20:53.878 2481 INFO neutron.agent.securitygroups_rpc [req-d6ad4800-cec8-4758-8232-fdcfcaf7e020 None] Security group member updated [u'ce582782-b451-4aef-b4c6-fde44c33e185']
2015-03-03 17:20:59.884 2481 INFO neutron.agent.securitygroups_rpc [req-a3c077cb-e4b6-469f-a8d6-d6c6119a270b None] Security group member updated [u'ce582782-b451-4aef-b4c6-fde44c33e185']
2015-03-03 17:21:00.832 2481 INFO neutron.agent.securitygroups_rpc [req-9d492160-f7c0-44ef-a1ee-bff5c7e89cee None] Security group member updated [u'ce582782-b451-4aef-b4c6-fde44c33e185']
2015-03-03 17:21:05.732 2481 INFO neutron.agent.securitygroups_rpc [req-3cd643a5-b8f7-4b52-80d6-52e4699ae59b None] Security group member updated [u'ce582782-b451-4aef-b4c6-fde44c33e185']

I was trying different things described on this forum, checking configs, etc. but without any luck. Not sure how to debug it.