Neutron is the Network as a Service (NaaS) layer of OpenStack. Part of Neutron is the LBaaS (Load Balancer as a Server) plugin which offers an abstraction layer that handles communication with load balancers. It is possible to configure the LBaaS modular with different drivers of load balancers.
The LBaaS agent normally runs on the same host as the L3 agent (the network host). This host can be seen as the gateway to your Cloud. The network must ensure high availability for production systems because if the host breaks none of the running instances on the Cloud are reachable. This scenario is a level 1 incident and each administrator or system architect must try to eliminate such SPOF services to guarantee maximum accessibility for your Cloud. read more