Nothing in libvirtd.log ... But a lot of things in the nova/compute.log, but unfortunately, it's like looking for a needle in a haystack :(

I searched for anything that mention error + the name of my instance. I found some, but nothing seems to be very clear :(

Here an example : 2013-11-27 10:04:02.410 3496 DEBUG qpid.messaging [-] RACK[4854710]: Message(properties={'qpid.subject': 'notifications.error'}, content={'_context_roles': [u'_member_', u'admin'], '_context_request_id': u'req-2d5a8ea8-99e4-4637-889d-1871c576431a', '_context_quota_class': None, 'event_type': 'compute.instance.create.error', '_context_service_catalog': [{u'endpoints': [{u'adminURL': u'http://192.168.10.140:8776/v1/c05dff13d2e6461dbd06f0fa0390cbdc', u'region': u'RegionOne', u'internalURL': u'http://192.168.10.140:8776/v1/c05dff13d2e6461dbd06f0fa0390cbdc', u'id': u'3d7c42356d5a42b2acd92a7a4136e1be', u'publicURL': u'http://192.168.10.140:8776/v1/c05dff13d2e6461dbd06f0fa0390cbdc'}], u'endpoints_links': []