openstack-ansible-security/doc/source/developer-notes/V-38516.rst

The Reliable Datagram Sockets (RDS) protocol must be disabled. Neither Ubuntu 14.04 or openstack-ansible enables this module by default, so the Ansible tasks in this role will disable the module.

To opt-out of this change, set the following variable to no:

security_disable_module_rds: no

NOTE: The module will be disabled on the next reboot.