Discovering versions from the identity service failed when creating the password plugin.
I have installed openstack on CentOS7.
When I installing keystone follow the install-guide to create the service project, the error occurred
# openstack project create --domain default \ > --description "Service Project" service Discovering versions from the identity service failed when creating the password plugin. Attempting to determine version from URL. Unable to establish connection to http://controller:35357/v3/auth/tokens: HTTPConnectionPool(host='controller', port=35357): Max retries exceeded with url: /v3/auth/tokens (Caused by NewConnectionError('<requests.packages.urllib3.connection.HTTPConnection object at 0x225f810>: Failed to establish a new connection: [Errno -2] Name or service not known',))
how can I solve this issue?