Description of problem: The Gateway CLI (gwcli) tool collects info about the ceph cluster on startup. For this to work we need a parameter set in the ceph.conf on all MON nodes mon_health_preluminous_compat = true This should be set on all MON nodes and the MON service restarted, before starting the gwcli. Version-Release number of selected component (if applicable): ceph-iscsi-cli-2.5-7.el7cp.noarch