Note that tripleo-ci appears to be hitting a similar problem: http://logs.openstack.org/79/329079/4/check-tripleo/gate-tripleo-ci-centos-7-nonha/0ec8e2d/logs/undercloud/var/log/glance/api.txt.gz#_2016-06-27_13_38_16_395
So I don't think this is environment-specific. It looks like there is an actual bug here, although it may not always reproduce.
Note that tripleo-ci appears to be hitting a similar problem: http:// logs.openstack. org/79/ 329079/ 4/check- tripleo/ gate-tripleo- ci-centos- 7-nonha/ 0ec8e2d/ logs/undercloud /var/log/ glance/ api.txt. gz#_2016- 06-27_13_ 38_16_395
So I don't think this is environment- specific. It looks like there is an actual bug here, although it may not always reproduce.