I can't comment for Arne, but I believe that my bug is the same issue(See comment #4, bug 1613947) and I have found that I can more reliably encounter the error when deleting an instance with multiple attached volumes. See reproduction steps in https://bugs.launchpad.net/cinder/+bug/1613947/comments/1
Jay,
I can't comment for Arne, but I believe that my bug is the same issue(See comment #4, bug 1613947) and I have found that I can more reliably encounter the error when deleting an instance with multiple attached volumes. See reproduction steps in https:/ /bugs.launchpad .net/cinder/ +bug/1613947/ comments/ 1
Hope this helps.