Comment 4 for bug 1595335

This option also appears required for creating instance snapshots when using ceph as a glance backend.

With the default:

<183>1 2017-08-15T20:34:06.223584+00:00 mcp3.lab014004.proxprod1.dfj.io glance-api 43552 - [MetaCloud@40521 levelname="DEBUG" component="glance-api" funcname="glance.api.v2.images" request_id="req-86916685-8f50-484f-be81-8d53df710d36" user="30d4c1531f6048dfb982f55163baa983" tenant="938b7c62b670480c8b8d315efd36d374" instance="" lineno="/usr/lib/python2.7/site-packages/glance/api/v2/images.py:795"] glance.api.v2.images There is not available location for image a5edc4c4-0027-4918-becc-c3f935ce846d _format_image /usr/lib/python2.7/site-packages/glance/api/v2/images.py:795

Setting `show_multiple_locations=True` lets snapshots work as expected.