Comment 2 for bug 1836018

FWIW, the reason I hit this was that charm-openstack-service-checks monitors all endpoints available, but glance-simplestreams-sync endpoint when use_swift=False (aka. product-stream is not pointing to the Swift API, but to the g-ss-s container IP) makes check_http return "connection refused" because nothing is listening on ports 80 or 443 (depending if http(s) is in use).