2012-08-06 15:24:29 DEBUG nova.utils [req-ec2fa89b-a125-4619-8013-79eda1a7758f 9663883e2d7b485eb1a4e8746ef62b8e f33437d869eb4c7783a62fdb070a0865] Attempting to grab file lock "iptables" for method "_do_refresh_provider_fw_rules"... from (pid=9131) inner /usr/lib/python2.6/site-packages/nova/utils.py:936