Config option sqlite_db is deprecated in 0a1bae9859079fb21a03716be947c5f1da6db0a2, and deprecate argument sqlite_db in method set_defaults in https://review.openstack.org/#/c/350945/, should use config option connection instead. For Ironic, we test database with sqlite in memory mode [1] as below: CONF.set_default('connection', "sqlite://", group='database') and don't use config option sqlite_db, so remove unused code. [1]http://docs.sqlalchemy.org/en/rel_1_0/core/engines.html#sqlite Change-Id: I52b4e31d112283b538275d818c6151e62d1ef78d